Audi S2 misfire on 3400 U/min Vems 1.1.69

[Kessman_real]

Hi,

I´m new in this forum and I run the VEMS Motronic in an S2 ABY with Audi Trigger. Now my problem, at 3400 U/min a have strong misfire with Trigger Error. At 4000 U/min all is OK. What could be the problem.

THX
Kessman

[Kessman_real]

I try but I think it will not help. The software is taken from a running car.

[GintsK]

Did you change the polarity of TDC sensor?

Gints

[Kessman_real]

I change the pins befor, after this the car only hat misfire at 3400 to 3500 U/min. I dry now to change the crank speed sensors.

[Kessman_real]

Now I have change the sensors and the problem is nearly gone. Only a few times the car have misfires at this engine speed. I'am on the way.

[quattroant]

im also having misfire issues on an ABY s2 coupe.

Ive reversed the polarity and ive moved the sensor closer by about 0.5mm by sanding the bracket down. If you do thip
Between 2000-3200 like a band of pure misfires. Regular and constant like running on four out of five cylinders.

Once on boost the misfires gone. It seems to be the point at which the boost gauge shows no vacuum and reads 0.
Once boost comes on all is well and part throttle low speed is ok.

Are you using the standard flywheel?

[gunni]

If you can rev through that rev range in boost then it´s not related to the crank sensor inputs.

[Kessman_real]

I use a lighter 3B flywheel and it seems to be the same. Nearly 3400 U/min is the point the car have 0 boost. Next week a drive the car to Peter Kowatsch, he will tune it.

[GintsK]

Can you post logfile of the problem?