I have a '02 996tt, with GIAC chip, EVOMS airbox and Fabspeed exhaust.

I just got a code P1250, "factory controled air fuel mixture" according to the ODBII reader.

I reset the code and so far (crosses fingers) it has not returned.

Any insite on this would be greatly appreciated. I have a track event tomorrow and want to compete.

Thanks in advance.

 

hmm i hope it has nothing to do with the evo airbox as i just purchased one....

 

I have had it for sometime now, well over a year. It would be strange for it to be the cause after so much time.

 

I have never had this but, if I were to guess it would be the MAF or O2 sensor.

 

did you try cleaning the MAF?

 

I have had MAF failures before and the code is different. As well as with the MAF you get check engine and PSM faulire lights. This time I only got the check engine, and the ODBII doesn't say "MAF" like it did when the MAF failed.

 

right but it could be dirty. it doesn't take much at all to foul the MAF. try some CRC maf cleaner from autozone....

 

P1250

Boost Pressure Control Deviation - Above Limit

Diagnosis conditions

• Boost pressure control active (operating condition close to full load)
• No faults in mixture adapation, pressure sensor, ambient pressure sensor, frequency valve

Possible fault cause

• Bypass flaps incorrectly adjusted
• Turbocharger faulty

 

Oh no bad turbo....must upgrade.

 

not ness. could be bypass valves