Hi,
I recently picked up an 04 MR2.
When revving the engine hard, some black smoke comes out of the exhaust. The exhaust is also lined with black soot. The engine smells slightly of petrol at times.
I recently picked up the car, it's been fitted with a stainless steel manifold and a TTE exhaust.
I believe that the previous owner had fitted the new exhaust fairly recently.
I read this thread here where someone had a similar issue after fitting a TTE exhaust: https://www.mr2roc.org/forum/index.php?topic=53476.0
Could it just be an issue with the new exhaust or something more serious like pre cat failure?
I've done around 200 miles in the car now and haven't seen any noticeable drop in the oil level.
Sorry if I've not provided enough information, I'm currently have very little knowledge on cars and am just trying to start to narrow down what the issue may be.
It's very likely the car is running very rich.
This can be due to an air leak on your intake, a duff MAF sensor (just behind the airbox), a duff o2 sensor or two, or a leak in your exhaust.
I'm guessing you're doing not much in the way of mpg
Hello and welcome.
We always like to start with the basics 1st.
What is the state of the air filter?
A simple but full service is a good place to start
Oil n filter less than £30.
Air filter 5-8
Set of plugs sub £10.
Maf clean. Free if you have car cleaner in stock.
any engine codes eml lights?
Does the eml come on then go off when starting?
nothing to do the the engine. But if thats not been maintained correctly. Check your tyres. If there cheapo ditch finders, budget for some proper tyres.
But 1st lets sort the smoke out.
Thanks for all your replies. I'll check the eml and air filter tomorrow morning.
It is an aftermarket K and N air filter. Could this be causing any issues?
If it were the O2 sensors or maf, are these costly to replace?
Quote from: Erudite on August 7, 2020, 18:32Thanks for all your replies. I'll check the eml and air filter tomorrow morning.
It is an aftermarket K and N air filter. Could this be causing any issues?
If it were the O2 sensors or maf, are these costly to replace?
It can choke the engine if it's dirty or over-oiled. If over-oiled it can also affect the MAF. There's lots of ifs so
@Ardent is spot on. Give it a good service and then you've got a clean slate to start with.
New plugs (12gbp)
https://www.sparkplugs.co.uk/ngk-spark-plug-bkr5eya-11
New air filter (14gbp)
https://www.partsforallcars.com/za001607
Clean the MAF with some carb cleaner
https://www.eurocarparts.com/p/wynns-air-intake-carb-cleaner-500-ml-555770650?type=shopping&gclid=CjwKCAjw97P5BRBQEiwAGflV6bkFUUD7Mhd4QDXpOjQPG4X4nuoG9J2-lSKsnMUl7e5LE_DsADpZaRoCkK4QAvD_BwE
If you can be bothered, a fresh oil and filter change
Then reset the ecu, and take stock of where you are.
If a new o2 is needed; they are about 65 new each. Or 30gbp I'd you don't mind crimping 3 wires of the connector onto the sensor yourself. No soldering needed.
From your 1st post it sounds like you haven't dealt with a maf before. If you don't know exactly what to do ask & someone will oblige.
Black smoke, fuel.
Blue smoke, oil.
White smoke, coolant
Pink smoke, too many mushrooms.
That's a keeper. :)) :)) :)) :))
Quote from: Erudite on August 7, 2020, 18:11some black smoke comes out of the exhaust. The exhaust is also lined with black soot. The engine smells slightly of petrol at times.
I recently picked up the car, it's been fitted with a stainless steel manifold and a TTE exhaust.
Could it just be an issue with the new exhaust or something more serious like pre cat failure?
I've done around 200 miles in the car now and haven't seen any noticeable drop in the oil level.
For now, keep a close eye on the oil. (even better after you have change it.) ;)
Pre cat wise. Good, you don't have any. Bad, you don't know what condition they were in.
How much black smoke?
Lets get a service done and go from there.
Does not matter, but dealer or private?
Maf Mod with wrong Injectors ?
https://www.mr2roc.org/forum/index.php?topic=51647.0
Thanks for all the help so far everyone, it's much appreciated!
I think I'm going to start this weekend by checking the kn air filter panel to see if it's dirty or over oiled (I'll probably also order the replacement filter that
@shnazzle linked as it seems more straightforward than having to re oil the kn filter), cleaning the maf and resetting the ECU.
These seem to be the most straightforward jobs I can do with the tools I have to hand.
I can then do a service once I can get over to my friend who has some tools I can borrow.
Could there be any detrimental effects in running the car in the short term while it has this issue?
Sorry again for my lack of knowledge, this is the first car I've maintained so I'm trying to learn as much as I can.
@Ardent it was a private sale. An American had bought it with the intention of exporting it to America. Only to find out that you can't export cars under 25 years old.
Quote from: Erudite on August 8, 2020, 11:48Thanks for all the help so far everyone, it's much appreciated!
I think I'm going to start this weekend by checking the kn air filter panel to see if it's dirty or over oiled (I'll probably also order the replacement filter that @shnazzle linked as it seems more straightforward than having to re oil the kn filter), cleaning the maf and resetting the ECU.
These seem to be the most straightforward jobs I can do with the tools I have to hand.
I can then do a service once I can get over to my friend who has some tools I can borrow.
Could there be any detrimental effects in running the car in the short term while it has this issue?
Sorry again for my lack of knowledge, this is the first car I've maintained so I'm trying to learn as much as I can.
@Ardent it was a private sale. An American had bought it with the intention of exporting it to America. Only to find out that you can't export cars under 25 years old.
You're making a good start. Tip - take the O ring off the MAF before your spray it with carb cleaner, as the solvent will swell and soften it.
I love your username, I do hope you're a pedant also?
Black smoke = too much fuel/too little oil, perhaps fuel injector issues
Update:
I cleaned the MAF. Along with cleaning and and oiling the k and m air filter.
This seems to have cured the black smoke problem.
However, the car is still running rich. If I have the window down with the roof up and the wind is blowing into the cabin there's a definite smell.
It also looks like there may be a leak on the engine?
(https://i.imgur.com/rPMS80O.jpg)
(https://i.imgur.com/KCHxUB5.jpg)
I'm thinking the next thing may be to get an OBD scanner and upload the readings. Would this potentially help to narrow down the problem?
That is definitely soot deposit where there shouldn't be.
Won't take much to find out where it's blowing there.
Either crack in that manifold runner or the gasket would be first guess. Easy sorted.
Sucking in air there could very well lead to the car overfueling as it's running fresh air over the o2 sensors.
Quote from: shnazzle on August 22, 2020, 21:03That is definitely soot deposit where there shouldn't be.
Won't take much to find out where it's blowing there.
Either crack in that manifold runner or the gasket would be first guess. Easy sorted.
Sucking in air there could very well lead to the car overfueling as it's running fresh air over the o2 sensors.
Thanks. I went and had another look this morning and took a couple of video's. That whole side of the engine looks pretty sooted up and grimey.
First video: https://streamable.com/0u1l6g
Second video:https://streamable.com/8ozpe3
Is there an easy way to check for the manifold/gasket blowing in that area? Do you think it could be more than that looking at the soot deposited on that side of the engine in the video?
A blowing exhaust gasket is pretty obvious, even with it idling you will be able to hear where a blow is coming from.
Quote from: AdamR28 on August 23, 2020, 12:38A blowing exhaust gasket is pretty obvious, even with it idling you will be able to hear where a blow is coming from.
Thanks, I started it up and couldn't detect any sign of blowing.
On checking the oil I noticed a smell of petrol (as though petrol was mixing with the oil). Could this point to an issue with the injectors?
As a side note I also noticed this mastic on the right hand side of the engine:
(https://i.imgur.com/JY5PAg3.jpg)
(https://i.imgur.com/hkRx4fM.jpg)
Quote from: Erudite on August 23, 2020, 13:47On checking the oil I noticed a smell of petrol (as though petrol was mixing with the oil). Could this point to an issue with the injectors?
This is almost certainly linked to your black smoke issue. From reading up, sounds like you've had too much fuel going in, and this surplus finds its way into your engine oil. It would be worth doing an oil and filter change asap.
I'm not familiar with the 1ZZ yet but that looks like the rocker cover / cam cover? If yes, then I would guess someone a bit over zealous with the mastic on fitment at some point - should be nothing to worry about, unless chunks of it have found it's way into the engine which is unlikely.
How do you know the car is running rich, just by smell?
Quote from: AdamR28 on August 23, 2020, 13:58Quote from: Erudite on August 23, 2020, 13:47On checking the oil I noticed a smell of petrol (as though petrol was mixing with the oil). Could this point to an issue with the injectors?
This is almost certainly linked to your black smoke issue. From reading up, sounds like you've had too much fuel going in, and this surplus finds its way into your engine oil. It would be worth doing an oil and filter change asap.
I'm not familiar with the 1ZZ yet but that looks like the rocker cover / cam cover? If yes, then I would guess someone a bit over zealous with the mastic on fitment at some point - should be nothing to worry about, unless chunks of it have found it's way into the engine which is unlikely.
How do you know the car is running rich, just by smell?
Yes at the moment just by smell. When reversing or if the wind is blowing from the back of the vehicle there's a distinct smell of fuel.
Thanks for the heads up re: the mastic. I'll go ahead and do an oil and filter change.
Righto! I don't know enough about the 1ZZ specifically to help any further, without an OBD code anyway, but I'm sure someone else will be along with more info soon.
On a daily driver with short distance drives, the oil tends to smell petrol.
The yellow lump ? The previous owner try to fix a broken gasket ?
At the end of second video it looks like water drops, wipe it with one finger and then rub it between two fingers to deicide if its oil or water.
Water maybe not that god, oil maybe the gasket is broken in some more places.
Quote from: Carolyn on August 8, 2020, 11:52You're making a good start. Tip - take the O ring off the MAF before your spray it with carb cleaner, as the solvent will swell and soften it.
I love your username, I do hope you're a pedant also?
Pendant, erudite, luddite, troglodyte, all words that may apply.
Quote from: shnazzle on August 22, 2020, 21:03That is definitely soot deposit where there shouldn't be.
Won't take much to find out where it's blowing there.
Either crack in that manifold runner or the gasket would be first guess. Easy sorted.
Sucking in air there could very well lead to the car overfueling as it's running fresh air over the o2 sensors.
I had a look using a feather attached to the end of a pencil and couldn't see any signs of air being sucked in around this area.
I think a lot of the soot in this area might be from an oil leak from the timing chain tensioner.
I picked up a cheap OBD bluetooth scanner and pulled some data from the torque app. I watched a lengthy youtube video on using the data for diagnosis but it only focused on lean rather than rich conditions. It hopefully helped me to understand what some of the readings were though.
This is the data I gathered so far (I was unsure how to take a log, so I took a few screenshots):
(https://i.imgur.com/ENLXAB5.jpg)
Is fuel trim bank 1 sensor 2 completely broken? Bank 1 x 1 and 2 x 1 look to be acceptable? But as can be seen they intermittently take a really rich reading. It will drop and then quickly pull back into range.
(https://i.imgur.com/MNms2LG.jpg)
(https://i.imgur.com/zkMFs33.jpg)
When reducing revs STFT runs lean and then when it adjusts it appears that bank 2x1 runs incredibly rich for a short period.
Also, do the O2 sensors look ok? 1x2 has little variance and when idle it sticks at 0.7v.
All readings were taken while stationary. Can anything be ascertained from them?
Re the blob of sealant on the cylinder head. Where the timing chain cover meets the head there's a very slight difference in heights at the joint so the OEM standard instructions call for a small bead of sealant at this point on either side before fitting the cam cover and seal.
Technically it only needs doing if the previous sealant has been removed, on a rebuild for example, it could be that someone has got a bit carried away fitting the cam cover and put a big dollop on.
You'd expect both short terms to fluctuate. That's kind of their thing.
But long-term you'd want close to 0.
I'm not sure what values you're reading on those F/T but values of 81 are definitely not right. A) it's not possible and B) they're calculated values so if it was 81 and ignoring A, it would be adding 81% more fuel in for that area and definitely be throwing an error code .. Unlikely. Methinks you've got the wrong PID selected.
You want "Fuel Trim Long Term" for bank 1 and 2
QuoteYou'd expect both short terms to fluctuate. That's kind of their thing.
But long-term you'd want close to 0.
I'm not sure what values you're reading on those F/T but values of 81 are definitely not right. A) it's not possible and B) they're calculated values so if it was 81 and ignoring A, it would be adding 81% more fuel in for that area and definitely be throwing an error code .. Unlikely. Methinks you've got the wrong PID selected.
You want "Fuel Trim Long Term" for bank 1 and 2
I think you were right. I've used another app and the data seems to be more accurate.
(https://i.imgur.com/Ky9LkGM.jpg)
(https://i.imgur.com/rUEopAR.jpg)
At idle.
(https://i.imgur.com/IjDAqqA.jpg)
At ~2000 revs.
That's better.
Could have a look at bank2 (cylinders 2 and 4) but all in all it's all still well within acceptable ranges
Thanks
@shnazzle much appreciated.
I've been out in it today and there's a loud noise coming from the engine at around 2500 revs (this is the sweet spot for it anyway).
The noise seems to occur after the car has been running for a while and when it's accelerating. Its even more pronounced when taking your foot off the accelerator.
I've tried to get a video of the noise here, quite difficult due to wind noise:
https://streamable.com/c4jjlg
I've checked the exhaust and the only heat shield that's at all lose is the one in the video below.
https://streamable.com/qz2fs1
I don't think that it's this causing the noise as it only catches very slightly on the surrounding metalwork and it's clear of the exhaust.
Any other ideas as to what it might be?
Youtube vids of rattles and noises are invariably useless! At least you tried.
Time to get your car in front of an educated ear!
Question -does it make the noise when in neutral sitting still? If not -it's probably not coming from the engine itself.
there are ways of pinning these things down..
Quote from: Carolyn on September 12, 2020, 18:09Youtube vids of rattles and noises are invariably useless! At least you tried.
Time to get your car in front of an educated ear!
Question -does it make the noise when in neutral sitting still? If not -it's probably not coming from the engine itself.
there are ways of pinning these things down..
Only at around 2500 revs, I'm not sure if it's just at that point or if that's when it's most pronounced. Once you accelerate past 2500 revs or let it drop below the noise tails off. It's very loud at this point though and can be heard of the engine/exhaust. It sounds like a reverberation in my opinion.
If it's in neutral sitting still the noise can't be heard.
Quote from: Erudite on September 12, 2020, 18:14Quote from: Carolyn on September 12, 2020, 18:09Youtube vids of rattles and noises are invariably useless! At least you tried.
Time to get your car in front of an educated ear!
Question -does it make the noise when in neutral sitting still? If not -it's probably not coming from the engine itself.
there are ways of pinning these things down..
Only at around 2500 revs, I'm not sure if it's just at that point or if that's when it's most pronounced. Once you accelerate past 2500 revs or let it drop below the noise tails off. It's very loud at this point though and can be heard of the engine/exhaust. It sounds like a reverberation in my opinion.
If it's in neutral sitting still the noise can't be heard.
A bit of sheet metal flapping about could well do it then!
On another thread
@The Arch Bishop said:
"Nasty rattle under throttle load (I think the exhaust is leaking somewhere rather than anything catastrophic)"
I said:
Not spoken about on here so much these days but the general rattle on OE exhausts is the heat shield on the main cat.
@Erudite Maybe like busses, wait for one for ages then two come along!
My 2p stab in the dark.
The spacer? inside the heat shield around the cat
Hi Erudite
I had a very similar issue between 2500 to 3000rpm.
2 minutes on an inspection pit and we found it. A piece of heat shield rattling away downstream of the manifold.
Hope it points you in the right direction.
Bit of an update on the car. I've finally found out why it's 'running rich', it's got a decat downpipe 😖
It was only when I started to look for the heat shields around the cat that I realised it didn't have one (this was also after googling 'catalytic converter' to see what one looked like).
I'm going to take it in to get a price for swapping out the downpipe and getting the original put back in.
Not really got any further with identifying the rattling noise. Its getting worse and after much googling I think theres a chance that a baffle has come loose (it's a Malian - possibly a rebranded top speed auto? ). If this is the case I'm thinking the most cost effective course of action may be to get the OEM exhaust put back on. I'll try to get a second opinion when I take it in for the price on the fitting of the cat.
Friendly mot tester to get that through
Quote from: Erudite on September 27, 2020, 17:58Bit of an update on the car. I've finally found out why it's 'running rich', it's got a decat downpipe 😖
It was only when I started to look for the heat shields around the cat that I realised it didn't have one (this was also after googling 'catalytic converter' to see what one looked like).
I'm going to take it in to get a price for swapping out the downpipe and getting the original put back in.
Not really got any further with identifying the rattling noise. Its getting worse and after much googling I think theres a chance that a baffle has come loose (it's a Malian - possibly a rebranded top speed auto? ). If this is the case I'm thinking the most cost effective course of action may be to get the OEM exhaust put back on. I'll try to get a second opinion when I take it in for the price on the fitting of the cat.
Slow down.
One option my be this.
https://www.cats2u.co.uk/3267-18
Much more £ friendly than OEM.
Plus you could possibly sell the down pipe to offset the cost to you.