After I got coolant in my intake, I got a few codes, including P0102 (MAF circuit low voltage). I swapped my engine for one with less mileage and have driven it about 50 miles since. The codes went away, except for P0102, even though I am using the MAF sensor from the newer engine. Moreover, I’m now getting P2196 (O2 sensor signal biased/stuck rich bank 1). I notice that one of the many causes of this code is a bad MAF sensor. Yet the car runs very well and I am not getting any of the signs of a bad MAF sensor, except the code. What could it be that is causing the P0102 to stay on?
Maybe there's an open or short in the MAF sensor circuit somewhere. You used the sensor from the new engine, but the old engine compartment wiring harness, right?
ChapmanF, Yes, the old harness. The electrical stuff is beyond my capability as well as the mechanic who did the work for me. How do I test the plug/wiring for issues? What’s weird is I don’t see any signs of a MAF problem, though, like starting, roughness, low fuel economy, or low power.
If you have a multimeter, or your mechanic does, one of you would start by following the "inspection procedure" in the repair manual (more info) for P0102.
