I replaced the IDM, it was bad. The check engine light blinks once, after unplugging the map sensor, light stayed on, did the same to the two other three wire sensors and they did not make any difference. so replaced the map sensor this weekend. The light still just blinks once when key turned on, the truck runs, just really bad. With this light not staying on when the key is turned on, does that sound like a problem with the PCM, could I have a problem with the PCM, its what I have been told.

 

you should very carefully inspect the plugs that connect to the valve cover harness. had one a short while back, give me problems. of the 5 wires that go to each plug, 2 go to the gp's, 2 go to the injectors to make them fire, and #5 or the center one is a return signal to the idm from the injectors. this connector in the plug was distorted, however it happened, but would not let her run.