Engine dies after full throttle

[Benquattro]

Try a different MAF first.
On Motronic a faulty MAF will cause exactly this... it is what happened to my car before the MAF went completely.

If possible just lend someone's MAF, takes very little time to swap...
It is not 100%, that it is caused by the MAF, so don't rush buying a new one before you try with another MAF.

Problem is; I don't know anyone with a s2 or 200 near me and vagcom is not showing odd parameters on the MAF or any other fault codes.

[Billman]

With vems I don't use the isv any more and I don't have this problem. My idle back then was perfect but the engine died.

[JP]

Hold lets clarify, Engine cuts out whilst accelerating or after having accelerated?

If it does it whilst coming to a hold after having accelerated hard then you need to start with cleaning the throttle body and then make sure the dampener is adjusted so that when you snap the throttle shut it doesn't instantly go to idle on the tps. Otherwise you end up with an implausible MAF signal where the value read by the MAF is outside the ECU's parameters causing the engine to stall. Happens a lot with old school turbo's like Calibra's aswell. Most garages will read the fault code as implausible MAF signal and assume the MAF is broken. Whereas implausible means the MAF is working but the signal is outside ECU known parameters for the given conditions.

If it happens whilst trying to pull away from a junction then 99% of the time it is the lambda probe going faulty, easily diagnosed by unplugging it and seeing if the fault goes away.

If it happens whilst coming on power on WOT then there is a lean running issue.

[Benquattro]

'If it does it whilst coming to a hold after having accelerated hard then you need to start with cleaning the throttle body and then make sure the dampener is adjusted so that when you snap the throttle shut it doesn't instantly go to idle on the tps. Otherwise you end up with an implausible MAF signal where the value read by the MAF is outside the ECU's parameters causing the engine to stall. Happens a lot with old school turbo's like Calibra's aswell. Most garages will read the fault code as implausible MAF signal and assume the MAF is broken. Whereas implausible means the MAF is working but the signal is outside ECU known parameters for the given conditions.'


-> The throttle body had been cleaned just before testing.
-> To avoid the problem, the damper needs to be turned to the throttle until it falls back horribly slow; so thats not an option.

[Pirvu Eugen]

Turbo Bypass valve? I had this with the valve membrane ruptured..
Hope this helps!

[terrybullwon]

This happend to my S2 after i had it mapped i never did get to the bottom of it.

Sorry i cant be of any help but there was a thread by Forum member Ross iirc?

[prj]

Problem is; I don't know anyone with a s2 or 200 near me and vagcom is not showing odd parameters on the MAF or any other fault codes.

VAG-COM on these ECU's won't show anything about the MAF, unless the MAF is completely broken.
There are some people on this forum from Belgium, perhaps someone feels like helping you?
You can use AAN and ADU MAF as well, they are the same as 3B.

Try unplugging the o2 sensor for starters... it does not cause limp mode on this ECU, so it is very easy to diagnose.

If you had a wideband gauge on your car, it would help lots as well...
Have you checked and made sure that your bypass valve is working correctly? If it fails, the maf might be oily and it will also stall...

[Benquattro]

I relocated my maf to the pressure side, and the problem is gone, car drives very nice now.

Think I have to search for someone in the neighbourhood to remap my ecu to maffles and beyond rs2 spec.
Don't think someone like that lives in Belgium

[prj]

That means you were running a BOV, not a recirculating valve and venting to atmosphere or your valve is shot. If it's the latter, then your turbo will soon follow suit.
Did you check your AFR at WOT with this "fix"? Your fueling will be completely off.
Why do you not solve the real problem?

Btw, I have not yet seen a single car that runs well in all operating conditions with the MAF on the pressure side. Have fun remapping.

[Ross]

I had this problem immediately after upgrading to a GT3071R, unforunately the only way I found to avoid it was lifitng lightly earlier at a junction and if it stalled, that gave me time to dip the clutch and bump it running just before I came to a stop. Actually started to become second nature

Mihnea mapped the car, and the next course of action was to relocate the MAF pressure side as it was expected as stated that the MAF was getting a screwed up signal. Unfortunately I had an accident in the car before having chance to solve the problem.

Oddly enough I've had it occur a few times in the RS2 now as well, when coming to a hard stop and the engine is cold - like when the lights turn on you.

[Benquattro]

That means you were running a BOV, not a recirculating valve and venting to atmosphere or your valve is shot. If it's the latter, then your turbo will soon follow suit.
Did you check your AFR at WOT with this "fix"? Your fueling will be completely off.
Why do you not solve the real problem?

Btw, I have not yet seen a single car that runs well in all operating conditions with the MAF on the pressure side. Have fun remapping.

I was running a Recirculating valve, a forge which is in working condition.
Haven't had problems with fueling.

I will remap the thing when I find someone though.

[prj]

I was running a Recirculating valve a forge which was in working condition.
Haven't had problems with fueling.

I will remap the thing when I find someone though.

You were venting air to atmosphere somewhere, or your MAF was installed incorrectly.
And about the remap - I hinted very strongly, that it is unlikely it will drive well in all conditions on the pressure side, even after remap.
That MAF was not meant to be on the pressure side, no amount of remapping will fix that.

[Benquattro]

You were venting air to atmosphere somewhere, or your MAF was installed incorrectly.
And about the remap - I hinted very strongly, that it is unlikely it will drive well in all conditions on the pressure side, even after remap.
That MAF was not meant to be on the pressure side, no amount of remapping will fix that.

I wasn't venting to atmosphere and my maf was installed correctly.

It is very fast and stable now, have not noticed any problems with fuel or other driving issues.

When/If I find someone to remap, I'll ask him/her to map to the TPS instead of the maf.

[prj]

I wasn't venting to atmosphere and my maf was installed correctly.

You know how they say "assumption is the mother of all ****ups"?
Air was entering or exiting the system past the MAF somewhere. I am quite certain of that.

When I find someone to remap, I'll ask him/her to map to the TPS instead of the maf.

And they will tell you that is not possible, because it isn't.

[Benquattro]

Ok, thanks.