2ZZ diagnostic help

Mark A · April 30, 2021, 09:26

I'm having a frequent problem and error codes on my 2ZZ and I'm wondering if anyone can give me some advice; here are symptoms.

The car is great to drive hits lift, runs smoothly, goes and sounds amazing but I keep getting an error codes of P1346 and P1349 with usually high idle once warm which if I blip the throttle it stops for 5 secs before jumping back up.

This is a zero miles engine (Brand new) I've used Techstream to test the OCVs and both stall the engine when switched on during idle, so I assume that's a positive test and indicates they are working.

I'll attempt to record some live data in Techstream.

I'm running out of ideas, the only thing I can think of is I've changed the oil pump gears and some how mucked the timing up, but looking at the pictures all seems OK?

https://photos.app.goo.gl/VJFYyxVQYhQBNEpZA
https://photos.app.goo.gl/6DMJoFVZmFNoXKXq6

Any other suggestions before I seek expert help? Another tests I can do with Techstream?

Joesson · April 30, 2021, 09:42

Quote from: Mark A on April 30, 2021, 09:26I'm having a frequent problem and error codes on my 2zz

The car is great to drive hits lift, runs smoothly, goes and sounds amazing but I keep getting an error codes

This is a zero miles engine (Brand new)

Any other suggestions before I seek expert help?

I'm far from being "expert help" but I am sure there are some on here that may be able to help.
But you say that this is " a zero miles engine ( Brand new) and that it " hits lift"
All I can advise is that in the olden day's a brand new engine was run in, with a gradual increase in revs over a period of miles, with changes of oil.

jonbill · April 30, 2021, 10:05

I think the high idle will either be a stuck iac valve or an air leak. nothing to with the error codes IMO.
I think you could try cleaning the ocv filters -
I used to get 1349 on my old 1zz, even though cam timing clearly did move. in the end I concluded that the cam movement wasn't fast enough or stable enough for the ecus liking. I replaced the engine in the end and the problem went away.
so not very helpful, sorry.

1979scotte · April 30, 2021, 10:15

If its brand new where did it come from and is there any warranty?

Mark A · April 30, 2021, 10:37

No warranty I bought a job lot of unused 2ZZ engines and a gearbox a couple of years ago.

My work around is just to have the Torque running constantly and just clear the error codes, once I've done this its fine for the rest of the day and about 50% of the time its a pending code. Its not my daily driver just a weekend hack so its not a major issue just annoying.

I have an ECUMaster waiting to go in so maybe that might resolve the problem but I will also clean/replace the IAC and double check the filter/screens.

Gaz mr-s · April 30, 2021, 10:40

I agree with the above. I hope it's run-in....
The IACV can be a pain. Once it's hot bleed the radiator. If you get air out bleed it again next heat cycle. And keep an eye on coolant level.

Gaz mr-s · April 30, 2021, 10:45

There are cheap IACV's from China on ebay. Apart from general gunge, the shaft inside the IACV has a miniature bearing which is only shielded, not sealed. It can get very sticky with grit, & is a pain to flush out.

Mark A · April 30, 2021, 10:51

Now you mention the coolant, the high idle is almost like its jumping back to the cold start strategy. I might have ago at bleeding system.

I'm pretty sure the throttle body and IACV is brand new but again I'll double check it, can I test the IACV with Techstream?

pistol pete · April 30, 2021, 12:17

I had exactly this on my mr2 2zz
It was the idle control valve. i went through 3 knackered ones before i found a working one..

Pete

Mark A · May 7, 2021, 14:52

Well partial success, took the throttle body off and checked the IAC, brand new and appears to move freely with no obvious faults. Rear VVTLi solenoid changed, MAF cleaned and general checking for faults.

The idle issues is better but not perfect, the idle stills sudden rises once warmed up but only for a second before dropping and occasional it seems to resolve itself after about 45mins of driving.

The EML and code P1346 still come on a frequent basis but as I mentioned before the car run like a dream so smooth I hit the limiter on occasions because I've not realized I'm up to 8K rpm.

I'm going to swap the MAF and check the for air leaks.

Dev · May 7, 2021, 18:51

It might be a good idea to check the camshaft sensor to make sure its working by tapping into it and seeing if its generating a strong 5volt signal.

Mark A · May 13, 2021, 18:16

Hi Dev

Gearing myself up for another diagnostic session and I'm being thick how does hitting the cam sensor generate a signal? This is the cam sensor on the inlet cam near the oil filler.

Dev · May 13, 2021, 22:29

I apologize wire tapping might not be a British term for probing.
In hindsight its probably not it as it would be a separate code if the signal was insufficient so there is probably no need to check it.

I would however check to make sure the wiring is correct. Often times its the wiring from the swap that creates issues. I know its a new engine but by chance did you install the VVT actuator on the intake cam?

The next thing I would try is swapping out the timing chain tensioner with a known good one even if its a new engine just a process of elimination before you have to measure the chain.

Mark A · May 14, 2021, 08:50

Thanks for the help Dev,

I started the car last night before taking it for a run, I checked the code after starting and it was showing P1346 pending which I cleared. I then drove the car for 30mins parked up for an hour and drove it again, giving it some stick, hitting the rev limiter a couple of times when I parked up again after 40mins I had no codes. I'm coming to the suspicion that its just a moody mare.

Dev · May 14, 2021, 12:46

Good to hear. Its possible that it just needed to be cleaned out with fresh oil that has been sitting for a long time to move a sticking actuator and or OCV valves to move freely especially if the engine was sitting a long time.

Mark A · May 14, 2021, 16:44

Hope so Dev, strange it still has a period during the "warm cycle" after about 20mins when I pull up it idles at 750ish before suddenly jumping to 1750 rpm then after a further 20 mins of driving it appears to settle into normal engine strategy. Its like its getting confused and thinks its on the cold start strategy or open loop, even though Torques shows normal operating +70 oC temp.
Does Torque show if the car is running open or closed loop?

Dev · May 14, 2021, 22:29

Quote from: Mark A on May 14, 2021, 16:44Hope so Dev, strange it still has a period during the "warm cycle" after about 20mins when I pull up it idles at 750ish before suddenly jumping to 1750 rpm then after a further 20 mins of driving it appears to settle into normal engine strategy. Its like its getting confused and thinks its on the cold start strategy or open loop, even though Torques shows normal operating +70 oC temp.
Does Torque show if the car is running open or closed loop?

I had a closed loop issue right after my swap that went away on its own so have others. It is believed to be due to the coolant not getting hot enough with in the time frame during the warm up cycle which would trip a code. Some believe its due to air bubbles that have to be flushed from the system. Some have also encountered an overheat condition with the 2ZZ taking in more air. It was discovered that the 2ZZ sits slightly higher than the 1ZZ that the water jackets tend to not be in line with the max line of the reservoir and could take in air. The solution is to slightly overfill the tank which will naturally dissipate any bubbles in the system overtime.

If you are not having any codes I would just drive it and maybe its just some teething pains that will work its way out once it all settles.

Mark A · May 29, 2021, 17:56

I also topped it up with oil as I don't trust the obx sump and 1ZZ dip stick and since adding just under a litre so it's filled just above the full mark the error 1346 error codes seem to have stopped.

Dev · May 29, 2021, 18:10

Quote from: Mark A on May 29, 2021, 17:56I also topped it up with oil as I don't trust the obx sump and 1ZZ dip stick and since adding just under a litre so it's filled just above the full mark the error 1346 error codes seem to have stopped.

Good to hear. There is a way to know the correct oil level of the 2ZZ. The 1ZZ dipstick tube if you remember has a rubber washer or spacer. Use that spacer on top of the dip stick to take a measurement of the oil. That will tell you the correct level.

Mark A · May 29, 2021, 22:17

Thanks Dev but I have a big wing OBX so I'm not sure it's completely the same.

Dev · May 29, 2021, 22:53

Quote from: Mark A on May 29, 2021, 22:17Thanks Dev but I have a big wing OBX so I'm not sure it's completely the same.

It should not matter since its the position of the oil level in relation to the pickup tube which is a constant regardless of which pan is used. The level is usually just before the top of where the oil pan meets the block where there is enough spacing so it doesn't collide with the crank. Even if you use a deeper or wider pan you can fill more oil but it should read the same on the dipstick in regard to how full its suppose to be. There were doubts on this a long time ago but the tuners have cited that the dipsticks are accurate with aftermarket pans however the dip stick level for the 2ZZ is different then the 1ZZ engine and that is why you use the rubber spacer so that you can add more oil to the correct level.
The danger is if you overfill the oil pan by adding an amount of oil based on the capacity of the pan as it is listed it might be over filled and hit the crank which would be bad and could even ruin the main seals.