No spark cranks but wont start
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Hey guys I have a 1996 jeep Cherokee country and a few weeks ago I started it and was letting it warm up then it died after a few minutes and would not start, it cranks good but has no spark. So here's all parts I've replaced... ignition coil, distributor with pickup coil sensor and cap n rotor, tested spark plug wires, cleaned all grounds, checked all relays and fuses, crankshaft position sensor, ignition switch, ecm, and cleaned the nss good and put dielectric grease in there. I'm out of ideas if anyone knows of something I've missed that would be very helpful thanks
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When replacing sensors on a jeep use oem I have learned this the hard way. After market crank shaft and cam sensors especially and o2 sensors. I have had the same thing happen when replacing my engine put all new sensors on it, it would run but not good put my old ones on it and it ran fine.
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When replacing sensors on a jeep use oem I have learned this the hard way. After market crank shaft and cam sensors especially and o2 sensors. I have had the same thing happen when replacing my engine put all new sensors on it, it would run but not good put my old ones on it and it ran fine.
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Sounds low to me but I dont know exactly what it should be I would think closer to 12v. Check your battery and see what it reads a good charged battery should read a little over 12.5v.
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There is a problem there; battery voltage should be the same as the coil B+ voltage. From your symptoms, I would guess, and it's only a guess, and you have done WAY too much guessing and parts cannon firing already, but without checking I seem to remember that the coil + is sent from the PCM. Have you pulled the diagnostic codes yet? this should have been your very first move. Then check fuel pressure, can you hear the pump prime when you turn on the key? And yes only OEM Mopar on the cks and ckps
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If the 12v were pulsed, it would be just about impossible to measure with a standard meter. You'd need an oscilloscope.
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There is a problem there; battery voltage should be the same as the coil B+ voltage. From your symptoms, I would guess, and it's only a guess, and you have done WAY too much guessing and parts cannon firing already, but without checking I seem to remember that the coil + is sent from the PCM. Have you pulled the diagnostic codes yet? this should have been your very first move. Then check fuel pressure, can you hear the pump prime when you turn on the key? And yes only OEM Mopar on the cks and ckps
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I think you should check the fuel pressure first, because it's the logical next step.
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Hey guys I have a 1996 jeep Cherokee country and a few weeks ago I started it and was letting it warm up then it died after a few minutes and would not start, it cranks good but has no spark. So here's all parts I've replaced... ignition coil, distributor with pickup coil sensor and cap n rotor, tested spark plug wires, cleaned all grounds, checked all relays and fuses, crankshaft position sensor, ignition switch, ecm, and cleaned the nss good and put dielectric grease in there. I'm out of ideas if anyone knows of something I've missed that would be very helpful thanks
You really replaced all these parts?? Distributor and PCM too?? No PCM in 1983.
Fyi, Its a PCM, not ECM.
It's a camshaft position sensor, not a distributor pickup coil sensor.
If it cranks and won't start, it's NOT the neutral safety switch, this just disables it from cranking, not starting.
Do you have 12v at the coil, and 5v at the tps, cts, cps, map and ckps?
Last edited by 97grand4.0; 01-17-2020 at 12:37 AM.
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Your profile says you have an SJ, which ended production in 1983.?
You really replaced all these parts?? Distributor and PCM too?? No PCM in 1983.
Fyi, Its a PCM, not ECM.
It's a camshaft position sensor, not a distributor pickup coil sensor.
If it cranks and won't start, it's NOT the neutral safety switch, this just disables it from cranking, not starting.
Do you have 12v at the coil, and 5v at the tps, cts, cps, map and ckps?
You really replaced all these parts?? Distributor and PCM too?? No PCM in 1983.
Fyi, Its a PCM, not ECM.
It's a camshaft position sensor, not a distributor pickup coil sensor.
If it cranks and won't start, it's NOT the neutral safety switch, this just disables it from cranking, not starting.
Do you have 12v at the coil, and 5v at the tps, cts, cps, map and ckps?