Van developed real bad miss. P0351 rec. coil pack circuit. Replaced coil pack. No change. Heard of faulty intake & clogged injectors. Sprayed Starting fluid around intake, no change in engine operation detecting no leaks. Disconnected fuel injectors one at a time at idle. Cyl. 1&4 no change in idle. Used screwdriver to listen to injectors. All getting ticking as it should be. Decided to change intake and clean injectors as a CYA move and was only about $30. Still no change. Ran compression check on all cylenders, 120-125 pretty even on all 6. Detected no fire from coil at 1&4 even with new coil. Checked PCM signal at harness plug with noid light for all 3 drivers. Grey wire (1&4) no signal, RY=good, UT=good, leading me to believe the PCM is at fault. Am I correct in this or could there be another gremlin in my engine?
P0351 Result of PCM failure? on 1996 Dodge Grand Caravan
Go to the PCM pin for the driver for the 1&4 coil, and back probe it for power to the PCM and if the PCM is able to pull that to ground or not. A testlight will work suitably for this, first connected to ground,. you should see power from the coil and it should flash off when the PCM turns the coil on to charge, and then if you didn't see power there you can connect the testlight to power to see if the command is there. It is possible that the driver inside the computer did fail, just prove that the wire inbetween the coil and the PCM didn't fail.