QuestionCar stopped running, had towed home. Got codes, 12 14 55. Checked MAP sensor, and appears to be good. Did not think MAP would cause total failure anyway. Checked cam sensor, 8v , and varying voltage between 1-4v while cranking. Checked crank sensor, 8v, no v on sensor leads while cranking. Replaced Crank sensor, now getting 8v, and it starts at 4v then drops to 0 while cranking. Did I just get a lemon sensor? Also noticed tach not working, but would occasionally jump, followed by rough running engine, check engine light would illuminate,but would reset when switched off then restarted,then the tach would quit again. Pulling hair out, and I cannot afford to lose them. Would appreciate any help.
AnswerHi Brian,
I agree with the approach you have taken. I'm wondering a couple of things though: did you leave the paper on the tip of the new sensor (it establishes the proper distance) and make sure it came into contact with the flex plate, held it in that position, and then tightenwd its bolt down to 105 inch pounds? If you didn't get the spacing correctly that may explain the flakey tach/rough running response (which is better than the no spark/no fuel no response that you had when the old one was still in place). You might want to get a new spacer from the dealer and try it again. Another possibility is: are you measuring the sensor voltage to the sensor ground (black/light blue wire) rather than to engine ground? You might also want to check the continuity of the gray/black wire to pin 32 of the 40-way black connector at the PCM and also check for the possibility of a short between that wire and the ground wire due to some rub through of the insulation between those two wires. (Also check ground wire continuity to pin 43 of the gray 40-way connector at the PCM). It seems that you just aren't getting a solid crank signal with the new sensor, and if everything above checks out you might buy a Chrysler dealer part if you didn't do that for the first one.
If you erase the codes (disconnect the battery) and you still get a 14 code after trying to run the engine for a bit, then I would not ignore the MAP or its wires (like a short between the 5V voltage supply (violet/white) and the signal (dark green/red), or a short of the signal to the ground wire black/light blue), though as you say it alone would not cause a no spark/no fuel shut down the way the faulty crank sensor has done.
I wonder though why no code 11 ever appeared when you had no spark/no fuel? When the engine first died, did you check for 12V at the dark green/orange wire at the 2-way plug of the distributor when you cranked it, and did you hear the fuel pump run for a couple of seconds when you turn the ignition switch to run? If the crank sensor were bad, you should still get 1-2 seconds of 12v at the dark green/orange wire at the 2-way plug-in to the distributor. before the ASD shut you down. You must be getting that voltage now though so that question is probably moot at this point.
So I hope this helps you thru the hair pulling crisis. Let me know if I have helped or not, please.
Roland
