158 replies to this topic

[Bargi]

I'm hoping some engine experts out there can help me out.

 

Recently switched to the Dutch ECU and finding cold starting takes a good 3-4 seconds for the engine to catch.

Swapping back to the CS mapped ECU it kicks over without issue.

Peter ran my ECU on his car for 2 weeks without issue but noticed the following

 

[color=rgb(31,73,125);font-family:Calibri, sans-serif;font-size:15px;]About your car starting bad, I did find something odd. I noticed, during the time the ECU was on your car with ObdTuner on it, it did do 35 crankshaft sensor position learning cycles. This is not normal, normally it does do this only once. This could explain the bad cold start behavior. The crankshaft position learning is done when the car is started for the first time, could it be you did disconnect the battery at night and reconnect it again before start up?[/color]

 

Another issue that's come about is on WOT in the higher rev range (about 4.5k up) the engine is hesitant and stutters as it's climbing.

It's not the coil pack as this was replaced recently and WOT below 4.5k it pulls fine.

 

It does seem strange the CS map runs fine. But I also found that I was getting P0141 with the new ECU, which Peter found was being blocked or checking disabled in the CS map, so possibly there's something else the map doesn't check.

 

Will be replacing the crank sensor this week which I'm hoping is the cause.

Just wondering if anyone has seen this before or peoples thoughts as to causes.

 

[Chris P Duck]

Did you ever get this sorted? What was it?

[Bargi]

No, but speaking with Peter at Zandvoort and he believes it's related to the throttle body. 

Out of the 100+ cars with his software there's 3 of us with the cold start problem.

At idle all other cars sit about 10% open while the problematic ones sit at 17%

One of the problematic cars was built identically with another car so waiting for them to swap them over to see if it makes a difference.

 

What problems are you getting?

[Nev]

Hmm, sounds like a tricky problem to isolate, best of luck.

[siztenboots]

Z22SE no camshaft sensor , so needs the intelligent coil pack to switch from wasted fuel injection to sequential multipoint during cranking

 

Anything different from your loom to others , in particular the parts that get extended?

[Chris P Duck]

No, but speaking with Peter at Zandvoort and he believes it's related to the throttle body.  Out of the 100+ cars with his software there's 3 of us with the cold start problem. At idle all other cars sit about 10% open while the problematic ones sit at 17% One of the problematic cars was built identically with another car so waiting for them to swap them over to see if it makes a difference.   What problems are you getting?

Exactly the same, was fine pre Dutch (which also went on the same time as the SC) now from cold I need to crank for between 3 and 10 seconds for it to catch. Sometimes the initial catch is lumpy and can take a bit of gas to stop it stalling. Once running its 100% fine. Sometimes hit starts are also a little rough but that's intermittent, cold start is always a ball ache. Peter also mentioned it may be TB related and said the position of the butterfly at idle was different from what he expected. He sent me 3 new maps to try as he thinks it's related to the feedback from the TB, still testing them but doesn't look promising

[Bargi]

Z22SE no camshaft sensor , so needs the intelligent coil pack to switch from wasted fuel injection to sequential multipoint during cranking

 

Anything different from your loom to others , in particular the parts that get extended?

 

this is true, but it's the crankshaft sensor that the error related to

 

Looking up how wasted spark works in the Ecotec I found this article here

Although possibly this applies more to the L61 in the US, but mine is a very early car, so potentially there are some differences. Chris what year is your car?

 

PCM Logic

This system utilizes a variable-reluctance CKP sensor mounted in the engine block near the integral crankshaft target wheel. The crankshaft has seven machined target notches, six of which are evenly spaced. The seventh crank notch is positioned about 55� ATDC of cylinders 1 and 4 and is used by the PCM as a sync pulse.

On 2000-01 ECOTEC engines, the CKP signal is fed to the electronic ignition module, which then outputs a reference pulse to the PCM, reflecting all of the CKP pulses. On 2002 and later models, the CKP signal is fed directly to the PCM. The PCM uses the CKP sync pulse notch to identify when the 2/3 coil is due up next to be charged. The engine always starts firing the 2/3 coil first upon cranking. Charging of the 2/3 coil always begins near the second crank notch. Charging of the 1/4 coil always begins near the fifth crank notch. You can actually see evidence of the coil firing events as feedback onto both the CAMOUT signal and CKP or REF HI signal. Notice the small triangular humps in the matching areas of both the signals shown in Fig. 6. The firing order is the typical 1-3-4-2.

[slindborg]

P0141 is post cat heater fault...

 

based on the other mild issues and the fact its not isolated (ok 3%< sample but still its something) I'd be considering a wiring harness change. Especially if changing the TB and/or Coilpack does not fix it.

What is odd, is that the non dutch SW copes, but then it might just be a little more tollerant of production stuff and you 3 have parts on the outer edges that Peter hasnt anticipated (no its not a dig, weve all tested stuff and gone with that answer and missed some of the freak tollerence bits).

[siztenboots]

you can get both wasted fuel injection and/or ignition

[NickB787]

I have a spare harness and 58mmTB if someone is still on an OEM TB, if you want to try, the harness I stripped back to check and recover nicely but it's usable ok just a bit messy, have and no time to sort it, EV1 plugs on it also

Edited by NickB777, 08 August 2014 - 11:33 AM.

[smiley]

Are all people that have problems on the 68mm with the wires changed?

 

[Bargi]

P0141 is post cat heater fault...

yep, the wires to the lambda were broken, the CS map ignored this, so possibly it ignores other things which is why it works ok.

based on the other mild issues and the fact its not isolated (ok 3%< sample but still its something) I'd be considering a wiring harness change. Especially if changing the TB and/or Coilpack does not fix it. What is odd, is that the non dutch SW copes, but then it might just be a little more tollerant of production stuff and you 3 have parts on the outer edges that Peter hasnt anticipated (no its not a dig, weve all tested stuff and gone with that answer and missed some of the freak tollerence bits).

Yes, potentially not all TBs are equal which hopefully after a swap will tell, if so he can take one and figure out the differences.

[Bargi]

Are all people that have problems on the 68mm with the wires changed?

As far as I'm aware yes

[slindborg]

are your wire changes crimped or soldered?

[Bargi]

are your wire changes crimped or soldered?

 

Dunno, whatever Vocky did

 

[Chris P Duck]

are your wire changes crimped or soldered?

  Dunno, whatever Vocky did  

I also had the loom swapped for a pre-modded one by Vocky and yes I also have the 68mm TB

Chris what year is your car?

2003

Edited by Chris P Duck, 08 August 2014 - 12:50 PM.

[Chris P Duck]

I wonder if I can nab Chill's TB for a test as his is SORN...

[smiley]

Maybe either Bargi or Mr Duck get's the camera out and takes some pixies of the TB wiring?

 

[FLD]

I wonder if I can nab Chill's TB for a test as his is SORN...

 

If not you're welcome to try mine.

[Chris P Duck]

Maybe either Bargi or Mr Duck get's the camera out and takes some pixies of the TB wiring?  

Not too easy as it's all been re-wrapped. I think logical order would be: 1 Change TB 2 Change Coil Pack? 3 Change wiring loom

If not you're welcome to try mine.

Ta. May well take you up on that FLD, assume yours is the 68mm as well?

Edited by Chris P Duck, 08 August 2014 - 01:02 PM.