Hi all,
I'm new to the club hoping for some assistance please.
Iv recently purchased a mk3 2000 that has had an engine rebuild at some point.
I'm having issues with both banks apparently running rich according to the OBD. Iv already replaced the 3 x 02s with Densos also replaced the MAF with a Denso as it was a cheap one installed. replaced plugs also
My short term fuel trims are -20 at idle on both banks.long term also massive -
Also maybe a unrelated problem is that the car idles fine but if I give it a Rev and then let it drop the car really struggles to find it's idle point again and it shakes for a few seconds until it does.
Any ideas would be very much appreciated.
Thank you
can you see what colour injectors it has? they're at the top of the engine, by the bulkhead
You've done the obvious stuff. Have you put in a new air filter?
After all that, it might be time to clean the idle air control valve and the throttle body.
A quick search of the 'how to' section will help you with that.
Quote from: M.Dub on September 30, 2021, 10:46Hi all,
I'm new to the club hoping for some assistance please.
Iv recently purchased a mk3 2000 that has had an engine rebuild at some point.
I'm having issues with both banks apparently running rich according to the OBD. Iv already replaced the 3 x 02s with Densos also replaced the MAF with a Denso as it was a cheap one installed. replaced plugs also
My short term fuel trims are -20 at idle on both banks.long term also massive -
Also maybe a unrelated problem is that the car idles fine but if I give it a Rev and then let it drop the car really struggles to find it's idle point again and it shakes for a few seconds until it does.
Any ideas would be very much appreciated.
Thank you
@M.Dub It does sound like your idle air control valve is a bit gummed up. Unfortunately not an easy fix as the throttle body has to come off.
You could try a couple of cans of EGR cleaner down the intake (after the air filter) while running to try to free it up.
Two small cans of Wynns EGR cleaner.
It's a bit tricky as the engine will undoubtedly stall a few times as you spray it but you start to get the hang of how much you can spray and how much to rev (by twisting the lever on the throttle body) without it stalling.
If that fails; throttle body off. This involves taking off two small coolant hoses that are connected to the idle air control valve which is a hoot.
Once off you can carefully remove and open the idle air valve and clean its insides, relubricate and refit.
It has to be refitted EXACTLY how it was. To the millimeter.
Best way is to use permanent marker and basically draw around the fitting where the IACV mounts to the throttle body.
I might do a little video on this as I've got a spare throttle body..
Both issues might be caused by an air leak after the maf. Did you lube the maf sensor 'o' ring? They can get damaged, but when fitting go in with a real 'plop'.
A common problem of fluctuating idle is the Idle air control valve fitted onto the throttle body. Sometimes it's influenced by the car not being used for some time. See this - https://www.mr2roc.org/forum/index.php?topic=60448.0
However, if you think it is the IACV, before you attempt the job, try bleeding the radiator at least twice. Vent screw is top left corner LOOKING at the car. Undo some of the frunk clips - only press down 2 or 3mm maximum. If pressed 4mm, guaranteed breakage.....but they are susceptible to age-hardening anyway. Get the coolant properly hot. Also, when the engine is cold, keep an eye on the coolant level....if it's dropping you may have a leak (front left bottom corner of radiator is most common) & the air in the coolant will mess with the idle.
A car pulling fuel like that is either a restrictive intake, restrictive exhaust or a bad fuel pressure regulator.
Based on the history that the engine was rebuilt it could have been due to pre-cat failure. If so then there is a possibility the main cat is clogged from the previous pre cat material. This has been a likely scenario in the past where the owner or the shop doesn't replace the main cat.
All of the above.
Big fan of starting at the easy cheap end of possibilities.
What condition is the air filter in?
Thank you all for the reply's
The injectors installed are green aftermarkets. I was thinking maybe change theses as the may be over fuelling?
Iv also considered the fuel pressure regulator so Iv ordered a replacement because I thought it might be running too high pressure.
Iv but a stock air filter system back on the car as it had a cheap aftermarket previously. I thought that may have been causing the problems. Iv installed a new panel filter.
The car had the original exhaust system on when I got it and the pre cats looked good and it doesn't use any oil. Iv now put a full stainless steel system on.
I'll try cleaning the idle control valve, is it worth me swapping the injectors or should maybe do everything else first?
I really want to get this car running right but don't want to keep throwing parts at it. With it having both banks rich that would indicate a common problem?
Thanks
As you have had the intake in bits, then checking that it's airtight would be a good one. It's highly unlikely to be injectors as it's rich on both banks (more than one would have to be dodgy), so it's more likely to be something that affects all cylinders.
Pressure regulator failures are not at all common, but it can happen.
Yea I thought the same on the injectors but I'm honestly running out of ideas now.
I'll re check the air intake when I try to clean the idle valve.
I did check my short fuel trims with the maf unplugged and one bank stayed negative and the other went +20 so that confused me?
You think is more chance of being restricted air flow some point after the maf?
Would a vacuum leak give me a lean condition?
Sorry for so many questions I'm just happy to have someone else input.
Thanks
what voltage are your b1s1 and b2s1 o2 sensors reporting? just wondering how rich it is.
Very rich, both are around 0.88v to 0.90v
Thanks for any help
what value is the maf reading at idle?
what values do you have for inlet air temp and coolant temp?
This idle is after a 50min drive sat on the drive afterwards
MAF - 26 g/sec
Intake temp - 37oC
Coolant temp - 91oC
I'd post screen shots but don't know how on my I phone
Thanks
Screen shots
That MAF value sounds very high to me, I'd expect 3-5 at idle.
Just thinking out load.
Is there any benefit to be had in disconnecting the battery for 20 mins to reset the ecu and monitoring what happens.
Has the maf been cleaned?
O ring sitting correctly?
Sorry think I missed a decimals point out on the MAF.
It's a new Denso MAF only been insane a week.
I'm seriously confused.
I'm thinking either fuel pressure is high or maybe a bunch of e bay injectors gone wrong??
looks like its running hot.
Installed lol sorry for the typo!
Honestly thank you for helping out, it's driving me mad! I bought this car banking on it having a solid engine but Iv only done 200miles and 100 of them was getting it home lol
Quote from: Carolyn on September 30, 2021, 21:10looks like its running hot.
You mean coolant hot?
This is her,
Not sure if the previous owner was a member, think he sort advice from here on the rebuild.
Quote from: M.Dub on September 30, 2021, 21:26This is her,
Not sure if the previous owner was a member, think he sort advice from here on the rebuild.
Don't recognise the car. Did see it on Facebook I think.
When yoy said 26g/s for MAF did you mean 2.6g/s? Because that's the value I often see.
Air leak after MAF before TB = unmetered air = run lean = add fuel (pos trim). So that's not it.
Air blockage = not enough air = rich condition = reduce fuel (neg trim). You said you've replaced it all.
Exhaust leak manifold = fresh air making o2 read lean = add fuel. You're not seeing it add fuel.
Air leak after TB?.. That would start to make sense. It pulls in X air, it reads X air, determined fueling, X air makes it past the throttle body... And then is lost? = overfuel.
Engine rebuild lead to leaky intake manifold?
If history is any kind of teacher.. It's going to be something very simple.
Try disconnecting a few things in sequence.
A) o2 sensors. Just unplug them
B) maf
C) throttle position sensor
Don't like seeing folks with issues.
But love seeing the team come together to help resolve it.
Is this an occasion when trying to find a vac leak, a squib of egr cleaner or similar, near, around the throttle or intake manifold would cause the revs to rise. Helping to pin down where the leak is?
Quote from: M.Dub on September 30, 2021, 21:26This is her,
Not sure if the previous owner was a member, think he sort advice from here on the rebuild.
Do I detect an early VW Camper in the background?
Nice.
an air leak after the throttle is still unmetered air, so would make it lean. (and idle would be high)
would be good to see pic of those spark plugs.
is it using much oil?
Yea
Quote from: Chilli Girl on September 30, 2021, 22:36Quote from: M.Dub on September 30, 2021, 21:26This is her,
Not sure if the previous owner was a member, think he sort advice from here on the rebuild.
Do I detect an early VW Camper in the background?
Nice.
[/quote Quote from: Chilli Girl on September 30, 2021, 22:36Quote from: M.Dub on September 30, 2021, 21:26This is her,
Not sure if the previous owner was a member, think he sort advice from here on the rebuild.
Do I detect an early VW Camper in the background?
Nice.
Yea my dads project, it's years in the making lol.
Quote from: jonbill on September 30, 2021, 22:43an air leak after the throttle is still unmetered air, so would make it lean. (and idle would be high)
would be good to see pic of those spark plugs.
is it using much oil?
Iv binned the old plugs but they was pretty heavy in carbon, I had misfire codes on all 4 that cleared when I changed the plugs. Iv had many issues to resolve with this car already!
My favourite was when it blew its fuel hose off behind the drivers seat and filled the car with fuel. The clip that holds the hose to the pump hadn't been put back on. Had to strip the whole interior. Good job I don't smoke.
No it doesn't use any oil that Iv noticed.
I wonder why the fuel pump hose had been taken off in the first place. If the pump has been replaced with an aftermarket one with too high volume or pressure might overpower the regulator 🤔
Iv thought the same, Iv got a second hand replacement pump etc on order so I was going to swap that out to see if it made a difference. Think the hose has been off because the car has previously been stripped and re built.
The car never fails to start first time, if I had leaking injectors would it flood and struggle to start?
Also if the injectors are too big cc
Would that cause a over fuel?
Definitely.
Argh why won't people just leave these cars alone eh
@Carolyn ;)
Both larger than standard injector (cc) size and higher than standard fuel pressure will make it run rich.
The ECU only controls the amount of time the injectors are 'on', and that amount of time is only valid if everything is as it was when the map was developed.
Quote from: jonbill on October 1, 2021, 13:47Both larger than standard injector (cc) size and higher than standard fuel pressure will make it run rich.
The ECU only controls the amount of time the injectors are 'on', and that amount of time is only valid if everything is as it was when the map was developed.
Perfect thank you all for your help I really appreciate it.
Looks like iv got a busy weekend ahead.
I'm going to replace the fuel pump etc and if that doesn't fix anything check a injector to see the cc, I'm assuming it's stamped on the side?
I'll change them if they are too big. Was the OEM 250cc?
Iv also got a OEM MAF from when I salvaged a standard air box so might give that a clean and see how it behaves.
Even tho everting Iv bought claims to be OEM / Denso I just don't trust them 100% so many fakes out there.
Quote from: M.Dub on October 1, 2021, 15:57Quote from: jonbill on October 1, 2021, 13:47Both larger than standard injector (cc) size and higher than standard fuel pressure will make it run rich.
The ECU only controls the amount of time the injectors are 'on', and that amount of time is only valid if everything is as it was when the map was developed.
Perfect thank you all for your help I really appreciate it.
Looks like iv got a busy weekend ahead.
I'm going to replace the fuel pump etc and if that doesn't fix anything check a injector to see the cc, I'm assuming it's stamped on the side?
I'll change them if they are too big. Was the OEM 250cc?
Iv also got a OEM MAF from when I salvaged a standard air box so might give that a clean and see how it behaves.
Even tho everting Iv bought claims to be OEM / Denso I just don't trust them 100% so many fakes out there.
The injectors tend to be colour coded. Standard are green, the next up (2ZZ) are yellow.
Hi everyone,
Just thought I'd update you all and hopefully this will help others having the same issues.
It was the injectors!
They looked decent enough and all the seals etc were in good shape but soon at I swapped them out for some new ones the rich running stopped and so did all the idle issues. Don't think they were leaking just over sized.
I have developed a misfire on cylinder 1 but I can't notice it when driving the car. Think it's flagging it up on idle. Could this just be the injector not seated properly and getting a small vacuum leak?
Cheers 🍻
Thats good news.
I'd think your misfire might be a fouled plug.
maybe take them out and clean them and try again?
what markings did the duff injectors have? same as the good ones?
Good news.
The collective strikes again.
The injectors had the same part number but different numbers stamped on the opposite side.
Not sure on the misfire as Iv not touched the plugs for weeks and I have only got the misfire code after changing the injectors.
Quote from: M.Dub on October 2, 2021, 21:21The injectors had the same part number but different numbers stamped on the opposite side.
Not sure on the misfire as Iv not touched the plugs for weeks and I have only got the misfire code after changing the injectors.
This is now ringing a bell actually... I remember someone doing this and then disappeared.
Can you check the number of holes on the injector nozzle?
Quote from: shnazzle on October 3, 2021, 08:38Quote from: M.Dub on October 2, 2021, 21:21The injectors had the same part number but different numbers stamped on the opposite side.
Not sure on the misfire as Iv not touched the plugs for weeks and I have only got the misfire code after changing the injectors.
This is now ringing a bell actually... I remember someone doing this and then disappeared.
Can you check the number of holes on the injector nozzle?
As I recall when we did the valve clearances on Helen's car, it reported misfires while it re-learned the valve timing, then they went away.
I'll dig the old injectors out the skip later and post a pick.
I'm just gonna drive it for a few days see if the misfire clears itself.
Did the previous owner say why they rebuilt the engine? Seems odd that they had to rebuild (which is usually down to possible oil burning and then the subsequent breakdown of the precats) but then didn't change the manifold and thus remove the precats?
No he never said, I asked him if he had removed the pre cats when I viewed it but he dint believe the whole pre cat story and thought the issues the roadster had was down to something else, he never said what he believed it was tho.
Fist thing I did was put a stainless system on it. The cats to be fair were in good condition from what I could see.
Think he just bought it as a projects
as he said he's been rebuilding engines a long time.
The old injector numbers
.
Quote from: M.Dub on October 3, 2021, 13:24.
Thought so...
We've had a discussion about these on here once before.
Supposedly "better" because they had a slightly higher flow and "better" spray patten.
I remained unconvinced... And now vindicated.
Bloody hell!!!
Guessing the injectors are rubbish?
I'd try a set of plugs. Cheap enough ,and running rich for so long won't have done them any good.
Changed them 100 miles ago
It didn't have the misfires before.
Can't get a break with this car lol
100 miles of super rich is long enough.
what are the fuel trims saying?
I'm not sure what they should look like but I'm guessing they should be somewhat consistent?
That screen shot is taken with the car just sat at idle.
Iv got a set of plugs somewhere I'll put them in this week sometime see if it helps.
It's currently got v power fuel and injection cleaner in the tank, you think that could be anything to do with it?
Thanks
fuel trims look fine, I'm with
@Carolyn
Trims looking good from here.
Is now the time for a(nother) set of plugs
£8 delivered and an ecu reset.
I would start looking at the coil packs. If they are the original they probably have deteriorated to the point where they are malfunctioning intermittently. Both age and time take its toll as the varnish from the windings wear thin. I have seen this kind of situation myself and with with other cars where a fresh set of OEM coils ends up being an instant fix (do not use cheap aftermarket coils). It can also be the cause of running slightly rich from being tired. Unfortunately there is no diagnostic method to test the coil out side of the engine however when the ECU registers a misfire the coils are suspect.
Our 2002 gets random misfire codes periodically, but always just at startup, and typically after sitting for days and in cool weather. While it is more rare, a single cylinder misfire might get recorded, but never the same cylinder. No definitive cause has ever been found, and after clearing the codes, the issue may go away for months. The random codes have never occurred after a warm startup, in normal driving, or if the idle RPM is held slightly high after a cold start.
The 2002 has been running the MAF mod with remanufactured yellow injectors for years.
Speculation is something is marginal, like slightly low fuel pressure at start, fuel drainback to the tank, a slightly weak signal from the crank sensor, or possibly slightly low voltage after sitting for a long period.
I would suggest clearing the code, and just driving it and see if it comes back and if there is any pattern.
Thanks everyone,
I'll try changing the plugs as a already have a spare set and the car has been running very rich until recently. If that don't work I'll run it for a while see if it disappears all tho it does feels horrible.
My confusion is why have the misfires only appeared since I removed the old injectors?
Could the over furling have masked the misfire somehow u think?
What's the cylinder layout?
Is number 1 on the right as you look at the engine?
Just changed the plugs but no change in the misfires, seems to pick it up on cylinders 1 and 2 mostly and intermittently on 3 and 4.
Feel like it's one thing after another with this car now.
You think this would have shown up on the old injectors, Iv got a second hand coil pack due so maybe if I put that on cylinder 1 and it clears the code then it must be that, just seems strange that they all failed at once soon as Iv changed the injectors?
A rich mixture is easier to ignite, so less misfires?
Now the mixture is much leaner, you need a fatter spark. If the coil packs are tired that could explain it.
You could swap the coils on 1 and 2 with the coils on 3 and 4 and see if the fault moves with them.
Don't get discouraged - you'll get there.
Yea maybe that sort of makes sense.
When I first got the car the spark plugs and coil pack were full of water, I change the plugs but not the packs, maybe they got damaged.
Guess I'll have to spend more money!
The reason I bought this car is because I thought the engine would be solid but I'm starting to feel like somethings seriously wrong.
Quote from: M.Dub on October 6, 2021, 18:06Yea maybe that sort of makes sense.
When I first got the car the spark plugs and coil pack were full of water, I change the plugs but not the packs, maybe they got damaged.
Guess I'll have to spend more money!
The reason I bought this car is because I thought the engine would be solid but I'm starting to feel like somethings seriously wrong.
Don't tell me - the plastic engine cover was missing? Nothing in an engine is that serious - everything can be fixed.
One step at a time!
No funnily enough! He probably just it on just before I got there tho lol.
Had a good inch of water in all 4
Changed coil packs for some salvaged Densos from a 2005.
Still misfires being reported although not immediately,
🤬🤬🤬🤬🤬🤬 honestly what more does this car want from me lol
Did you try my suggestion of moving the coil packs?
It's probably time to check the valve clearances and do a compression test.
Yea did that but to be honest the original coil packs looked tired so thought that may have been the problem.
I'm thinking the same now regarding compression, just don't know how to do it myself
1st off.
Do you have a compression tester tool?
When you changed the coil packs, did the misfires stay on the same cylinders?
Hi guys sorry for the late reply.
Yea still shows misfire on cylinder 1 and 2.
I don't have a compression tester but think I'll order one later and see what it says.
I'll watch a few YouTubes in the meantime try and learn how to do it.
I'll post the results when I have them.
Quote from: M.Dub on October 16, 2021, 10:07Hi guys sorry for the late reply.
Yea still shows misfire on cylinder 1 and 2.
I don't have a compression tester but think I'll order one later and see what it says.
I'll watch a few YouTubes in the meantime try and learn how to do it.
I'll post the results when I have them.
Key things really are to make sure you pull the injector fuse so that you're not drowning the cylinders,and to floor the accelerator while you're cranking.
Just looking online (eBay, Amazon) and seeing some really nasty looking testers.
Anybody know any decent ones that don't cost the earth?
Quote from: M.Dub on October 16, 2021, 10:28Just looking online (eBay, Amazon) and seeing some really nasty looking testers.
Anybody know any decent ones that don't cost the earth?
For the number of times you'll use it, a cheapo will be fine.
https://www.ebay.co.uk/itm/383134349347?_trkparms=ispr%3D1&hash=item5934963823:g:ftgAAOSwMipfQ3hL&amdata=enc%3AAQAGAAACoPYe5NmHp%252B2JMhMi7yxGiTJkPrKr5t53CooMSQt2orsSQuF9OYLb3wphIAOfpJK8RibMbdJuvyxZLt9KA7AsBXyyIUTwRgu7JWpt2ON1ucIMb1%252F1dqMAoRjEBq%252FRURmfzaMcsg3qpj36khhZsDu9w%252BoxpfEKwXuXUkJkzEPS9%252B0%252BwAUgDTxDesHl8leQuTwRcA1MhWYMzjKbus%252Bg7EdGy02YaupdiIJoQ%252FKWoE%252BPvOKSoUffIeL6xAFFKPMlwpELYfGy6M0aflpX2uXdIcQ4IQa1bxHZ12dBnpqZEYXIJBCr4O1m79LTBuNrRwIcfm3NXdjZQsh66S30hhu06VNIeINhnOP96oDQUnKyYcz%252F6I6IGRx%252FMLI1SRO%252Fmm1X%252F7d%252B6ZYbe%252FBH0eu6E3s7QZAg821qXLKBUPB6iNWmiw4n%252B8kbIs7x%252FOMdadLKdV9FmxtD8Zr2Bh4RMPxPg5tANo%252BEk90XE3LcGkabB6LW2WpmFeEj57k078vwplWHvxxC3%252BvR5g4r1XRnSjLqn94O%252BzEbLH1Alx7k34rYna%252Byq0QuyVlYy2kdboRG57HFhBx4UwPyUZ4V5nLTv6ozpEJlr%252B6wvJVZYAvAH8htl3EXcaW%252BFu9Czd6%252FgB9Rz%252FlEknGzOHE0FAUV9EQexGaXbQUDloDyaCtXWDdmXdDZsiy2bA%252FR%252FJWWmQlLBHG7cgoyDvgZrJWR%252B%252BVKWcPoK0THhlqcpftJf%252BN3CCNmswrPNR7b78to5omeUymciBhuY0SeH9f5YGzekH1ald5TO1djG88gCg0s%252FJ7Tuje4zAcY6yZjPmCnIrs2A%252BggyaoD6y62evmdtBBINnaOIyMLJd56%252FkNraLDIvGi4ZE8AL3Iel6m5zmsm5pruatrLDdkrX9w%252FetutJeP0Ag%253D%253D%7Campid%3APL_CLK%7Cclp%3A2334524 (https://www.ebay.co.uk/itm/383134349347?_trkparms=ispr%3D1&hash=item5934963823:g:ftgAAOSwMipfQ3hL&amdata=enc%3AAQAGAAACoPYe5NmHp%252B2JMhMi7yxGiTJkPrKr5t53CooMSQt2orsSQuF9OYLb3wphIAOfpJK8RibMbdJuvyxZLt9KA7AsBXyyIUTwRgu7JWpt2ON1ucIMb1%252F1dqMAoRjEBq%252FRURmfzaMcsg3qpj36khhZsDu9w%252BoxpfEKwXuXUkJkzEPS9%252B0%252BwAUgDTxDesHl8leQuTwRcA1MhWYMzjKbus%252Bg7EdGy02YaupdiIJoQ%252FKWoE%252BPvOKSoUffIeL6xAFFKPMlwpELYfGy6M0aflpX2uXdIcQ4IQa1bxHZ12dBnpqZEYXIJBCr4O1m79LTBuNrRwIcfm3NXdjZQsh66S30hhu06VNIeINhnOP96oDQUnKyYcz%252F6I6IGRx%252FMLI1SRO%252Fmm1X%252F7d%252B6ZYbe%252FBH0eu6E3s7QZAg821qXLKBUPB6iNWmiw4n%252B8kbIs7x%252FOMdadLKdV9FmxtD8Zr2Bh4RMPxPg5tANo%252BEk90XE3LcGkabB6LW2WpmFeEj57k078vwplWHvxxC3%252BvR5g4r1XRnSjLqn94O%252BzEbLH1Alx7k34rYna%252Byq0QuyVlYy2kdboRG57HFhBx4UwPyUZ4V5nLTv6ozpEJlr%252B6wvJVZYAvAH8htl3EXcaW%252BFu9Czd6%252FgB9Rz%252FlEknGzOHE0FAUV9EQexGaXbQUDloDyaCtXWDdmXdDZsiy2bA%252FR%252FJWWmQlLBHG7cgoyDvgZrJWR%252B%252BVKWcPoK0THhlqcpftJf%252BN3CCNmswrPNR7b78to5omeUymciBhuY0SeH9f5YGzekH1ald5TO1djG88gCg0s%252FJ7Tuje4zAcY6yZjPmCnIrs2A%252BggyaoD6y62evmdtBBINnaOIyMLJd56%252FkNraLDIvGi4ZE8AL3Iel6m5zmsm5pruatrLDdkrX9w%252FetutJeP0Ag%253D%253D%7Campid%3APL_CLK%7Cclp%3A2334524)
Done the tests
All 4 range from 165 psi to 170psi
Is this abit low?
Don't know how accurate the test kit is
Quote from: M.Dub on October 21, 2021, 13:50Done the tests
All 4 range from 165 psi to 170psi
Is this abit low?
Don't know how accurate the test kit is
Hard to tell with a compression tester because of too many variables of how it was tested. Cold engine vs warm engine and other things vary the test.
The most important thing is if the values are close between each cylinder it is assumed that its fine.
If you find one or two cylinders that vary greatly from each other that is when you do the wet test.
I'd say it was just about warm, I'd had it ticking over for 10mins but only tested it 20mins later.
Still getting the misfire codes tho albeit intermittent. I'm thinking it's possibly the fuel pressure dropping slightly when the engine is shut off or idling or that the replacement injectors I put in arnt quite right. Think Iv checked or changed everything I can now.
Car drives fine but I ideally want everything perfect before I take it to a track.
just for completeness, what are the fault codes your getting?
P300
P301
P302
P303 (less often)
P304 (less often)
They pend for a few drives then confirm, mainly p301,p302
Iv took it out earlier and had no codes at all not even pending.
It's intermittent,
Thanks
Interesting that its 1 and 2. not on same o2 sensor.
I'd try swapping injector 1&3 and then coil pack 1&3 to see if the misfire follows.
I'm also getting a intermittent P420
But I'm assuming this has something to do with having fitted a sports Cat?
Iv also read that the misfire could falsely raise this so not wanting to mess with anything else until I get rid of the misfire.
I'm thinking it's the injectors as Iv already changed the coil packs and it changed nothing.
Screen shot
fair enough, so swap injectors 1&3 and see if the misfire follows.
So, Iv swapped all the injectors round sat the car at idle for 10mins and sure enough misfires logged 1,2,3!
So just to recap Iv done the below.
Changed plugs
Changed coil packs
Changed injectors
Done compression (circa 165-170 psi on all 4)
Changed all 3 lambda
Changed MAF
Fitted new exhaust system and sports cat
Change fuel pump etc
Checked for vacuum leaks (cant find any)
I honestly don't know what else to do other than give up and accept it's just part of this car, feeling defeated now.
165-170 is a bit down. Might be worth a leak-down test on a warm engine.
Or you could check your valve clearances. Valves not sealing well is well down on the list, but you ARE well down on the list!
Tight valves will show up when warm...
I still think it's injectors. I took them out and re installed a cheaper set just to see if I got lucky, I didn't! The car started running rich all over again so I binned those and re installed my old ones.
Now Iv installed them in a different order the most common misfire has move to cylinder 1 and 3 when previously it was 1 and 2? I'm thinking I have another poor set of Injectors, they don't run the car rich but maybe they are bad in some other way?
Does anybody know where to get a decent set? I can't keep buying sets and hoping they work properly.
you could buy a cheap ebay injector tester and rig up something to check their flow volumes, between those two sets your bound to have a 4 good ones.
there are youtube videos of people doing this.
or you can send them off to be reconditioned (not cheap)
I was thinking the same with having 4 good ones between the 8 I have but seems 4 of of them run the car super rich, 2 of them work ok and the other 2 cause misfires. I never imagined it would be so difficult to find such a common part for this engine.
Iv enquired with breakers on eBay and everytime I get told they've already sold the originals.
You can buy new ones. I think MAG engines still sell reconditioned calibrated ones also. I bought yellow 2ZZ injectors from them and they were fine. If you keep installing used unproven kit, you'll be chasing ghosts!
https://www.ebay.co.uk/itm/192561585668?hash=item2cd5909e04:g:HQ4AAOSwA3dYMDdE (https://www.ebay.co.uk/itm/192561585668?hash=item2cd5909e04:g:HQ4AAOSwA3dYMDdE)
Thank you,
Will get a set of these and hopefully that's the ends of it lol
Appreciate your help
Thought recognised this seller, I have some receipts from the previous owner for some of the rebuild parts.
Quote from: M.Dub on October 28, 2021, 17:45Thought recognised this seller, I have some receipts from the previous owner for some of the rebuild parts.
They're in Dubai. I've dealt with them a few times. Very reliable.
So I got the new injectors installed went to start the car and nothing! Car wouldn't start, didn't even try. The injectors aren't opening at all. Just to check I reinstalled my old ones and car started fine.
Any ideas?
This pic is one of the new ones from MAG.
That's strange. I'll look at my spares tomorrow.
how did you confirm the injectors aren't opening at all? stethoscope?
Compared them to a set of known good injectors I've got. Everything looks the same
I'm totally confused to be honest.
I didn't use a stethoscope or anything like that. The engine turned over fine just didn't even try to start just as if there was no fuel at all.
I put my old ones back in and it fired up first time so I can only assume they did not open, maybe I'm wrong I'm no expert lol.
If I plug them in loose and turn the ignition can I check them that way?
Quote from: M.Dub on November 3, 2021, 20:51I'm totally confused to be honest.
I didn't use a stethoscope or anything like that. The engine turned over fine just didn't even try to start just as if there was no fuel at all.
I put my old ones back in and it fired up first time so I can only assume they did not open, maybe I'm wrong I'm no expert lol.
If I plug them in loose and turn the ignition can I check them that way?
The fuel rail will just spit them out. Petrol everywhere.
Sorry I meant I'd leave current injectors installed (bolted into rail etc) and just unplug the power. I'd then plug the new ones onto the power sockets and have someone turn the engine over. Maybe then I could listen to see if they open and close?
Not that you should really have to do all this when you've just bought them. Feel like I'm cursed with this car
I think its really unlikely that 4 new injectors from a reputable seller just don't work at all, none of them.
so I wonder if maybe they need longer cranking to fill with fuel etc before the engine fires. how long did you crank for?
Tried so many times the battery was almost flat. When I removed them there was fuel pressure in the rail.
I know thought the same, I don't understand why these don't work but my old ones do. It can only point to the new injectors being the problem.
I know you're all probably sick of this thread now
Is there any kind of a 'seal' for keeping out dirt in storage? Something physically blocking them?
Iv had the same thoughts but it's hard to see. It dose look like somethings in there but not sure if it's suppose to b or not.
Perhaps contact MAG and see if they use anything to seal them? If they do, and they've been exposed to full pressure fuel...
I already have contacted them but not holding my breath tbh.
I'm pretty sure they've had full pressure at them. I'm guessing that's bad?
Lol you mean I will never get them out?
Is there any way to add a video clip?
Iv tested all the new MAG injectors along side some old ones and hooked them up to a battery. I can hear the solenoids operate in all my old injectors however the MAG injectors do nothing at all.
Quote from: M.Dub on November 4, 2021, 15:52Is there any way to add a video clip?
Iv tested all the new MAG injectors along side some old ones and hooked them up to a battery. I can hear the solenoids operate in all my old injectors however the MAG injectors do nothing at all.
Generally people upload clips to YouTube or upload it to a online drive and link it.
Unfortunately we can't afford enough storage to accommodate people's videoclips :(
A simple check if you have a multimeter is to check the resistance of the injector across the connector pins. I checked a good set of green injectors and got 13.6 ohms on all of them. The Toyota spec is 13.4 – 14.2 ohm at 20°C (68°F)
(https://i.imgur.com/rVebqLD.png)
Funny enough I tried this out of curiosity only checked 1 of the MAGs it was 29ohm
Quote from: M.Dub on November 4, 2021, 17:42Funny enough I tried this out of curiosity only checked 1 of the MAGs it was 29ohm
Sounds like they sent the wrong injectors.
Quote from: Beachbum957 on November 4, 2021, 18:28Quote from: M.Dub on November 4, 2021, 17:42Funny enough I tried this out of curiosity only checked 1 of the MAGs it was 29ohm
Sounds like they sent the wrong injectors.
That's what I was thinking. They sent me the wrong pistons once. They put it right and I ended up with two sets of pistons.
Very odd that they have the same part numbers.
Unless mine are wrong as well :)
Even if they were the wrong ones for the MR2 they should still open when connected directly to a 12v battery?
Iv messaged them so hopefully I'll get a refund or another set sent out.
Honestly tho, I'm sick to death of changing injectors I never want to do it again!!
Hopefully 4th set lucky
Quote from: M.Dub on November 4, 2021, 20:28Even if they were the wrong ones for the MR2 they should still open when connected directly to a 12v battery?
Iv messaged them so hopefully I'll get a refund or another set sent out.
Honestly tho, I'm sick to death of changing injectors I never want to do it again!!
Hopefully 4th set lucky
Don't ever touch my car, please 😀
😂😂😂
Just for the record It's all the parts fault
Mine are all 14
Iv managed to free 2 of them up by just persisting with the battery so they now open and close, not that I'm planning on using them id just thought I'd let you know.
I suppose its possible they are coated inside with some anti corrosion goo or something and it needs to get washed off. perhaps soak them in petrol?
I think some plastic film has got shot into them. Maybe just soak them in petrol over night?.
Had a response from MAG, they acknowledge there may have been a problem with the injectors and are sending out a new set.
Good service from them in the end 👍
I must admit I'm not convinced that installing these injectors will fix the issues I'm having, Iv got a feeling it's something more sinister.
If these don't fix it given Iv exhausted all the simple options what else could it be and how would I diagnose it?
If 2 cylinders keep misfiring all the time and the other 2 misfire rarely given all 4 have similar compression, new plugs,good coil packs, new injectors, Iv check the electrical connectors.
What could it be?
I'm mindful that the engine has previously undergone a rebuild and concerned its something internal?
Thanks
you could check the cam timing.
Have you checked the valve clearances?
I haven't done either of those, Iv never done anything like that and don't really have a clue how to do it.
Is it something I could do myself with some Googling? Are they difficult to do?
Quote from: jonbill on November 7, 2021, 17:26you could check the cam timing.
If this was a problem would it be able to effect the cylinders individually or would they all be misfiring together at all times?
Thanks
Quote from: M.Dub on November 7, 2021, 19:40Quote from: jonbill on November 7, 2021, 17:26you could check the cam timing.
If this was a problem would it be able to effect the cylinders individually or would they all be misfiring together at all times?
Thanks
they are all misfiring aren't they? other variations (valve clearance?) might account for why 2 cylinders misfire more than others.
Yes they are, 1+2 pretty much all the time but cylinder 3+4 much less often.
Quote from: M.Dub on November 7, 2021, 19:30I haven't done either of those, Iv never done anything like that and don't really have a clue how to do it.
Is it something I could do myself with some Googling? Are they difficult to do?
Firstly, I'd wait until the injectors arrive and see if they cure the problem. If not:
Take a look at:
https://www.mr2roc.org/forum/index.php?topic=66483.0 (https://www.mr2roc.org/forum/index.php?topic=66483.0)
Don't worry about actually removing cams, you don't need to do that. The first part of the instructions has excellent photos that will show you how to remove the cam cover and check the cam timing.
Decide if that's a job you want to tackle. If you do:
Feeler gauges can be had from your local parts shop. They are cheap get two sets of metric ones.
The last picture shows the position the cam lobes should be in (on cyinder #1) to measure the clearances. The inlet valves (the cam with the big hub on one end) should be in the range of .15 to .25 mm. Select a .2mm feeler gauge and try to slide it under the cam (between the cam lobe and the flat steel bit below the lobe). The exhaust clearances should be in the range of .25 to .35 mm. Select a .3mm gauge and try to slide it in.
If a gauge will not slide in, select a thinner one (.15mm for inlet and .25mm for exhaust) and see if they slide in. If they don't, the gaps are too tight they will prevent the valves from closing properly when the engine is warm.
The feeler gauge should be a snug sliding fit in the gap. If the gauge is very loose, try thicker gauges to estimate the gap. I doubt big gaps will be your problem, as the valves would be very noisy.
To measure the rest of the clearances, rotate the engine to bring both cam lobes up on the cylinder you want to measure next.
If you Do have tight valves, see below. Decide if THAT'S a job you want to tackle (I recommend against it). It might be time to get a decent mechanic involved.
Further pictures and instructions can be seen at:
https://www.mr2roc.org/forum/index.php?topic=65009.0 (https://www.mr2roc.org/forum/index.php?topic=65009.0)
While you're in there, it pays to replace the cam cover gasket. Don't buy a super cheap one!
I have been following this thread as I sometimes get a random misfire code and may have missed a few things, but it looks like you have checked almost everything that is listed in the shop manual. It might be a good idea to get a scan tool that gives actual values, not just codes and verify the values for coolant temperatures, RPM, and fuel trims look correct. Fuel trims will give a good indication of the performance of the injectors and even the O2 sensors
But a commonly overlooked item is the crankshaft position sensor. Normally, if it fails the problems are more severe, but the possibility of a weak signal (or loose connection) has been covered previously on the forum and in numerous articles. Here are some links
https://www.mr2roc.org/forum/index.php?topic=47813.msg554334#msg554334 (https://www.mr2roc.org/forum/index.php?topic=47813.msg554334#msg554334)
https://www.mr2roc.org/forum/index.php?topic=14573.msg181048#msg181048 (https://www.mr2roc.org/forum/index.php?topic=14573.msg181048#msg181048)
https://www.underhoodservice.com/misfire-crankshaft-camshaft/ (https://www.underhoodservice.com/misfire-crankshaft-camshaft/)
https://www.yourmechanic.com/article/symptoms-of-a-bad-or-failing-crankshaft-position-sensor (https://www.yourmechanic.com/article/symptoms-of-a-bad-or-failing-crankshaft-position-sensor)
Since the engine was out and rebuilt, verify the sensor is properly installed and the connections are tight. A less likely possibility is a camshaft position sensor. The manual has resistance values for both, so it is possible to do a basic check with a multimeter.
Crankshaft Sensor 1,630 ohm – 2,740 ohm cold, 2,065 ohm – 3,225 ohm hot
Camshaft sensor 835 ohm – 1,400 ohm cold, 1,0600 ohm – 1,645 ohm hot
Throwing parts at a problem can get really expensive, but many shop manuals have the same advice on testing electronic components "replace with known good parts". If the sensors seem out of range or are suspect, perhaps someone has some you can try without buying new.
Thanks for the advice I know it's been a long thread. I'll try the injectors once I get them and then see how brave I feel if they don't work.
Quote from: M.Dub on November 8, 2021, 13:54Thanks for the advice I know it's been a long thread. I'll try the injectors once I get them and then see how brave I feel if they don't work.
Don't feel bad. Rather this thread go on for 10 more pages and end up in a positive result than you going quiet, not having a running car and us left in wonder :)
And as they always say... You're never going to be the only one with this question so it's worth it.
Wrt the valve job, I did the measuring in about an hour and the actual valve job in a parking lot with the help of Carolyn at our last national day :)
Hi all,
Just a quick update, I installed the replacement injectors from MAG and so far managed 60 miles of misfire free driving.
I'm still not overly confident this will last but so far so good.
Thanks for all the help.
It will be fine. You figured it out and got the result!