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Tom in NH

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About Tom in NH

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  1. Hi Moses, Spent the last couple days tracking and tracing everything I could. Narrowed the major draw down to what appears to be the ignition switch. I got a draw (bright light)at the alternator, but not the thick red wire going to the single post. That tests fine, but rather at the brown/tan resistance wire which according to diagrams I have seen leads to yellow ignition wire and what I have read suggests a faulty ignition switch. Also got a draw at the green lead running from the hot post on the starter relay which again, diagrams say leads to ignition. Have just replaced ignition
  2. Hi Moses, Thank you for your full and complete responses. And yes, you mentioned the battery right up front. Had it tested, thought all was good.... Update. New battery shows 11.9 volts this am. Given your explanation, believe we have found the smoking gun. Now have to find the actual culprit. So, that means battery drain when Jeep is "off", correct? To confirm, with Jeep in off position I disconnected ground and ran a test light from ground cable to neg post and it light up. So, now I disconnect accessory cables at battery (we have 2 led light sets and an oversized positive
  3. Hi Moses, Yes, double checked the scale on the multimeter when I checked the lead from ecu pin 27 and it read a legit .5-,6, but what you say makes sense. My multimeter is a relatively cheap version and is digital. I have read that analog meters are sometimes better at reading signals that change quickly. Idle didn't change after cleaning cps, but it was idling well prior. The Jeep runs quite well ... until it stumbles which is sporadic and infrequent. Even less frequent stalling and no start immediately after stalling only a couple of times in the last 6-9 months since this issu
  4. Hi Moses, OK, backprobed the orange wire at the ICM that connects to pin 27 on the ecu. When running, I get a kind of bouncy reading of between .5 and .6 volts. No pattern or regular timing to the variation. So if it is supposed to be a 5 volt sine wave, I'm assuming that means I should get a 5 volt reading alternating with zero at regular intervals? Also pulled my cps and it was oily like it usually is when I check it. Cleaned it and area around it, retorqued valve cover. Ran it for a good half hour, and even though the coil is getting 14+ volts at the + lead, it was not hot I
  5. Moses, Another thought. So, if 14+ volts on the yellow lead to the ICM is normal and expected, then is it possible the Autozone brand ICM could be the culprit and is just not up to the task? As they are warrantied parts I have been simply replacing with the same. Because, as I think this through, I am also getting 14+ volts at the + lead of the coil, so the ICM is not doing anything to step the voltage down before it sends the power to the coil. Like I said, electrical is not my strong suit - swimming as fast as I can here to keep up, but learning and enjoying it. Thank you.
  6. Hi Moses, Wow. Thank you for the thought and detailed comments. A lot here. A few comments and then I will test what I haven't yet tested and report back . With key on, engine not running, I get 12 + volts (basically static battery) at connection A (yellow lead) and at the + lead on coil. With engine running, I get the 14+ volts at both. I was aware of the 5 volt sine wave function (though didn't really understand it's operation until your explanation - electrical is not my strong suit), but I have not tested it running. I got zero volts at key position run with jeep not ru
  7. Hi Moses, Thank you for your response and thoughts. Some more info and answers to some of your questions. I am reasonably sure the grounds are good. Will check in the am, but went through them after reading another thread on your site when this problem first cropped up. I paid particular attention to the ground by the dipstick. I also added grounds a couple years ago and checked and cleaned those. I have had both battery and alternator tested at autozone and they check out good. I am on my 3rd coil in the last 18 months (warranteed, but still ...). This last one is what got me t
  8. Greetings, Have a 1989 YJ with the 2.5l TBI. Have had a sporadic idle, stall problem. Verified fuel delivery and injector performance, tested and/or replaced all sensors and IAC motor. Cleaned throttle body, checked for vacuum leaks. Kept looking over at the coil/icm assembly, but thought "no, just replaced those not too long ago." Long story short, tested the coil - badly out of spec. Changed out both coil and icm and finally (slow learner here) checked voltage entering coil. Constant 14 =/- volts at startup and run. Checked with my daughter who drives the vehicle and she confirm
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