Hi,

Today suddenly the car started running very rough (similar to when I lost my high pressure fuel pump on my BMW), I got an yellow engine light and a "take car to visit workshop" message. I restarted the engine and the CEL disappeared, but it still ran badly it stalled a few times at traffic lights.

Once home I checked with Duramteric and had several errors from many non-engine system regarding voltage being low. The only engine related error was:

B0120 Exhaust gas temp sensor circulation internal bank1 sensor1, No signal/Communication.

I know I had this error for a while (saw it weeks ago and never did anything since it is going to the dealer soon for a cable replacement) so I do not think it is the "issue" I have now.

Why isnt there any more engine codes? Since I got the CEL in dash something must have been registered, right?

Is Duramteric not giving us access to all errors stored?

I will test the car later today myself and try to get it to the official Porsche dealership in Stockholm on monday (I am under full warranty).

 

Anyone with ideas?

I been suggested to check coils, but wouldnt that be more a problem at higher revs and under boost?

 

Coils will affect it at any speed/rpm....Expensive labor to change.... But given the info you shared, is your battery good? If voltage is bad, all sorts of stuff can happen..Worth checking anyway..

Good luck.
DC

 

My WAG is the alternator is weak, or goes weak after a bit of running. Then the car is running off of mostly battery power or battery power only.

The car will act very strangely with likely seemingly unrelated errors/warning lights. There can be a CEL but maybe not.

The engine can die, but after a bit can be restarted. In some cases this engine off time "resurrects" the alternator and all is ok for a while until the alternator again grows weak or quits working altogether.

To replace the battery let alone the alternator without a definite or very high confidence level diagnosis is wastefully expensive, so get the car to a shop for a proper diagnosis.

 

I think that the MAF needs cleaning or replacing.

 

So I have checked alernator voltage, its 14,7V during idle. Seems good to me. The car has been running fine for two days now so I am a little confused, I'm not a big fan of intermittant errors

 

Would this manifest itself all the time or would it be a coming and going problem?

 

Since Sweden is a cold country, car battery's only last 3-5years at the most, its prob not a bad idea to change it before this winter hits.