I have a 1997 Boxster with problems, any help would be very appreciated.
I am pulling OBD II Codes P1123, P1125, P1128, P1130 (one says rich one says lean). What is happening with the car is when you clear the codes and start it it runs really rough for about 5 minutes, the RPM's bounce between 600 and a 1000 (once it even died). When you start to go it seams as though its on the verge of backfiring, after about 10 minutes of driving it it smooths out mostly and then the CEL will not come on again after about an hour of driving time, after the light comes on it seems to run smoother and with more power, but if you step on it the power band falls really flat after 5,000 RPM. Ive been told a couple of different possibilities, 1. O2 sensor, 2. Throttle position sensor (Throttle Switch Valve) or 3. fuel pressure. Has anyone had any experience with above problem and if so what was the fix. Thanks in advance for any help or suggestions.

 

Sounds like a Maf sensor problem to me.

 

Great another fix. I have read some of your other reply's though and I will go with yours. Thank you very much for responding.

 

The MAF came in today and I installed it.... Holy crap! My car has had this problem since I bought it a few months ago, Ive taken it to the dealer and another garage and none of them correctly diagnosed the problem. Tha MAF did the trick and added massive amounts of power to the car, this thing goes through the RPM range so quick now you have to be careful not to bump it up against the rev limiter. Thanks very much for the suggestion and keep staying in those holiday inn expresses!

 

Glad it was an easy fix [sm=icon_cheers.gif]