QuestionQUESTION: 'I have a 1994 Chrysler lebaron 3.0 liter V-6. Its been sitting in the barn for about 2 years now, I drove it down there and parked it myself. Some guy wants to buy it, so I went down there a few weeks ago, and it turns over, but wont fire. I have power to the coil, but no power to the distributor cap. I replaced the coil, cap and rotor, new spark plugs, even re-timed the engine, thinking that maybe the 2 year old timing belt had jumped a cog. I am wondering about the powertrain control module, but I would like to know if there is some type of test I could do to at least verify that the module isn`t functioning, before I shell out the clams to replace it. I have also looked for evidence of rodent damage to the wiring, and can find absolutely no evidence of chewed up wiring. Even under the dash looks very intact. Any help here would be greatly appreciated.'.
ANSWER: Hi Jeff,
How about trying the ignition switch to get any fault codes that are stored in the memory of the pcm:"on-off-on-off-on and leave on" doing that in 5 seconds or less elapsed time. Then watch the check engine light, which remains 'on', to see it begin to flash, pause, flash, etc. Count the number of flashes before each pause. Then repeat the process to be sure of an accurate set of flash counts. Tell me the counts in order of appearance and we'll go from there to see what might be wrong.
When you say 'power to the coil' do you mean 12v on the dark green/orange wire, while you are cranking it?
How about the fuel pump, do you hear it hum for about a second when you turn the key to the run position.
Sorry for the delay but I just found your question on the 'pool' where it had be referred by another expert.
Roland
PS Please 'rate' my answer and where you see the question about a nomination of me for 'volunteer of the month' consider a 'yes' response. Thank you
---------- FOLLOW-UP ----------
QUESTION: The fault codes I got were as follows: (The number represents the number of flashes in succession, the "p" represents a pause between sets of flashes)
1 p 2 p 3 p 5 p 3 p 7 p 2 p 4 p 5 p 5.
Power to the coil meant exactly what you said, 12v at the green/orange wire while cranking, and 12v power to the black wire directly adjacent to the green/orange wire during cranking as well, but no power out to the distributor cap, which was why I chose to replace the coil.
The fuel pump is working in response to the key position.
Thanks for your expedient response to my questions thus far.
AnswerHi Jeff,
None of those codes would cause a no spark. The 12 means that the battery was disconnected recently, the 35 says that there is an issue with the radiator fan relay control circuit, the 37 says there is an issue with the torque converter lock-up solenoid of the transmission, and the 24 says there is an issue with the throtte position sensor circuit.
The pulsing of the driver for the coil may be faster than you can detect with your voltmeter but since you aren't getting spark then you could check the continuity of that coil plug wire to the pcm at pin 19 (gray/black). That wire has to be shorted to ground briefly by the pcm to produce a spark.
The throttle position sensor signal wire (orange/dark blue) goes to pin 22 of the pcm. Check it for continuity and for not being either shorted to 5v or to ground, which is the voltage on the other two wires of its plug. Check its harness to be sure the insulation hasn't melted through.
I don't see any pcm problem here so check out the wires first. Nor is there a code for the engine rotation sensors which would be the other cause of a no spark.
Roland
PS Thanks for the rating.
