The 1994 NA 945 I recently purchased is throwing a 2-3-1, 2-2-1, and a 2-3-2 code intermittently (Bosch injection). Today I drove it about 2 hrs at 70-75 mph and the Check Engine Light (CEL) turned on about half way through. When I parked, the ECU spit out a 2-3-2, 2-3-1, and 1-1-3 code. I reset the ECU and to see if it was an injector leak, sprayed a bit of WD40 in each injector seat to see if I could tell an idle speed change and found none. Now that the car is cold, the CEL turns on immediately after starting and throws a 2-3-1 and 2-2-1 code.

The car sometimes idled poorly cold, stalled, and had low power until warm. I thought it was a mass air flow sensor problem or o2 sensor, but after changing my oil to full synthetic, it now idles fine cold (the old oil looked used but I didn't see anything too terrible). There is a bit of hesitation off idle when cold, so I still think the o2 sensor needs to be replaced.

The other codes, however, indicate an air leak somewhere in the system. After spending some time on the FAQ, I'm unclear where to start looking. I cleaned the throttle body a few days ago and still had the poor cold idle/hesitation problem.

Any suggestions? Hope everyone and their loved ones have a happy and safe Thanksgiving.