Alright gentlemen here is the latest. So parts replaced (all oem parts): plugs wires dizzy cap rotor ignition coil distributor ignition pickup and cps. Still no spark. Checked all fuses and qiring and nothing exposed or blown. Any ideas?
CF Veteran
Do you hear the fuel pump prime when you turn the key? If not, for kicks and giggles, try jumpering the Asd relay. It eliminates it as an issue, or shows its faulty.
CF Veteran
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FYI: The manufacturer calls that a Switch Plate in the parts catalog. The FSM refers to it as a Camshaft Position Sensor (CMP).Originally Posted by perez1989
Check to see if your jeep has a pick up coil in the distributor. That also controls the spark on the ignition.
CF Veteran
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Can you describe how you determined you are not getting spark please.Originally Posted by old big red
Alright gentlemen here is the latest. So parts replaced (all oem parts): plugs wires dizzy cap rotor ignition coil distributor ignition pickup and cps. Still no spark. Checked all fuses and qiring and nothing exposed or blown. Any ideas?
Did you perform the tests in my previous post?
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When you replaced the coil did you make sure the surfaces of the coil, and the coil mount, are clean and capable of grounding to the engine?
Ok well here im going to state that very good point and I apologize for overlooking this comment. No I did not check that. Update though. So battery was bad and fuel pump relay is bad but asd relay is fine. Found a link on how to bypass those so I tried it and that's what I found. So tomorrow im going to check the coil grounding. But if it isn't grounding does that harmit at all?Originally Posted by CCKen
In the previous post wiring diagram, did you notice that the coil is engine gounded. That is, the coil itself is grounded to the engine.When you replaced the coil did you make sure the surfaces of the coil, and the coil mount, are clean and capable of grounding to the engine?
CF Veteran
See post #13.
You never did say how you determined that you are not getting spark, nor if you did the tests in post #13.
You never did say how you determined that you are not getting spark, nor if you did the tests in post #13.
Pulled out a plug hooked it back into boot grounded it out and no spark. Took wire off coil and cranked and no spark between coil and wire
CF Veteran
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You need to determine if you are getting 12 volts to the coil and if the PCM is pulsing it to ground.Originally Posted by old big red
Pulled out a plug hooked it back into boot grounded it out and no spark. Took wire off coil and cranked and no spark between coil and wire
If you don't have voltage and/or ground pulse there may be a PCM driver problem or voltage supply problem. That is to say that the ASD relay is functional.
CF Veteran
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Is that decimal point 12? Are you sure you have your meter set to 20 volts DC?Originally Posted by old big red
Ok gentlemen here ya go. So come to find out im only getting .12 volts to my ignition coil. Where do I go from here.
Yes it is a decimal 12 and yes im positive. I have 3.8 coming out the pcm but a quarter that actually gets to my ignition coil. I tried to take a picture but the downloader wouldn't let me
CF Veteran
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How did you determine you have 3.8 volts coming out of the PCM? Originally Posted by old big red
Yes it is a decimal 12 and yes im positive. I have 3.8 coming out the pcm but a quarter that actually gets to my ignition coil. I tried to take a picture but the downloader wouldn't let me
I think you should get another Voltmeter (Digital) and check your voltages again. Sometimes a bad Voltmeter will send you off chasing your tail with bogus readings.
Edit: The 12 volt power source to the coil does not come from the PCM. It comes from the ASD relay via fuse F21 in the PDC.
The PCM provides the ground driver for the coil.
The wire carrying the 12 volt source is the Dark Green.Orange tracer wire at the coil. The PCM driver wire is the Gray wire.
Volt meter is good. Even tested a few circuits on my wife's car and got exactly what it was supposed to be. So your telling me the dark green wire with the orange tracer coming from the pcm does not go to the coil. Tested it multiple times and every time it came back with the same reading