Here it goes again
dksob81
03-11-2005, 12:48 PM
You know I thougth I had this damn Ignition problem stomped. Well I got a new problem I've been sick the last couple days so i haven't driven the jeep since the morning before yesterday, well today I tried the remote starter to warm the jeep up and it turned over quickly then quit (this has happened a couple times with this cheap remote starter system) so I went out and tried starting it and it just cranked and cranked, so I turned the remote control module off and trie startrting it still nothing. Well had my g/f out there cranking while I checked for spark and various things well NO SPARK, first thing that came to mind bad ignition coil (but this one is less then 2 weeks old), well changed the ASD with a few other relays still NO SPARK, So I went ahead and got another ignition coil and still nothing. Right Now I Am At Aloss. I need some help - what else could it be, I never ask for much guys, so please help.
JoJo
JoJo
dksob81
03-12-2005, 12:07 AM
***UPDATE***
I think I may have tracked te problem......
OK the book (haynes, FSM) says the CamShaft Position Sensor Control the timing of the Fuel injectors, but doesn't mention anything about the Ignition Coil (SPARK), except for in one of the test in the FSM. well anyways I tested the Camshaft Position Sensor (via HAYNES) and I am not getting any voltage supply from the PCM, so I am gonna run a jumper to the PCM and see what happens I will update 2morow and let everyone know how it went.
ALSO, when I d/c the Cam Sensor Electrical Connector and try to start the jeep the CHECK ENGINE light doesn't stay on like it should. It comes on for a couple seconds like normal then shuts off - when it should stay on telling me that there is a problem. HUMMM WIERD, maybe this has something to do with that wire as well. I will find out.
I think I may have tracked te problem......
OK the book (haynes, FSM) says the CamShaft Position Sensor Control the timing of the Fuel injectors, but doesn't mention anything about the Ignition Coil (SPARK), except for in one of the test in the FSM. well anyways I tested the Camshaft Position Sensor (via HAYNES) and I am not getting any voltage supply from the PCM, so I am gonna run a jumper to the PCM and see what happens I will update 2morow and let everyone know how it went.
ALSO, when I d/c the Cam Sensor Electrical Connector and try to start the jeep the CHECK ENGINE light doesn't stay on like it should. It comes on for a couple seconds like normal then shuts off - when it should stay on telling me that there is a problem. HUMMM WIERD, maybe this has something to do with that wire as well. I will find out.
mikec041
03-12-2005, 03:40 PM
The CPS does affect the coil firing
I had a 87 Cherokee that the wire to the cps melted (great routing over the header between firewall and Engine) and would short when hot then work fine when cold.
When shorted the coil would not spark.
I had a 87 Cherokee that the wire to the cps melted (great routing over the header between firewall and Engine) and would short when hot then work fine when cold.
When shorted the coil would not spark.
dksob81
03-13-2005, 12:23 PM
***UPDATE***
Well upon some wire tracing I found that the cam Sensor was not getting any battery voltage (8 volts) like it should and figured there must have been a broken wire somewhere so I ran a jumper (cut wire at PCM and cut housing on wire at Cam Sensor connector) wire from the PCM to the Cam Sensor. still no voltage so I checked for voltage at PIN #7 NOTHING, so I disconnected my jumper wire and hooked up another PCM from a 4.0L and I got VOLTAGE, that lead me to believe my PCM was bad. then today went to a couple salvage yards to try to find one and came up short. So I went back and was messing around and hooked my PCM back up checked voltage and to my surprise it had 8 volts (8.9 volts to be exact), then I hooked up the jumper wire and voltage dropped to 0, hummmm disconnected it back up to 8 volts.
Now I think the K25 White/Black (PIN #7) wire going from the PCM to the cam Sensor/CrankSensor must be broken somewhere and grounding out. ONE THING - I know if it was grounding out it would effect voltage on the other end. but would it shutdown voltage all together? - Say I checked voltage before the broken part of the wire and grounded it would it kill the voltage throughtout the whole wire or just after the broken part?
ELECTRICAL IS NOT MY FORTAY.
Well upon some wire tracing I found that the cam Sensor was not getting any battery voltage (8 volts) like it should and figured there must have been a broken wire somewhere so I ran a jumper (cut wire at PCM and cut housing on wire at Cam Sensor connector) wire from the PCM to the Cam Sensor. still no voltage so I checked for voltage at PIN #7 NOTHING, so I disconnected my jumper wire and hooked up another PCM from a 4.0L and I got VOLTAGE, that lead me to believe my PCM was bad. then today went to a couple salvage yards to try to find one and came up short. So I went back and was messing around and hooked my PCM back up checked voltage and to my surprise it had 8 volts (8.9 volts to be exact), then I hooked up the jumper wire and voltage dropped to 0, hummmm disconnected it back up to 8 volts.
Now I think the K25 White/Black (PIN #7) wire going from the PCM to the cam Sensor/CrankSensor must be broken somewhere and grounding out. ONE THING - I know if it was grounding out it would effect voltage on the other end. but would it shutdown voltage all together? - Say I checked voltage before the broken part of the wire and grounded it would it kill the voltage throughtout the whole wire or just after the broken part?
ELECTRICAL IS NOT MY FORTAY.
dksob81
03-13-2005, 10:02 PM
***UPDATE***
BLAH BLAH BLAH.
Got the jeeper runnin again, it was all caused by the CPS wire hitting the exhaust manifold and burning the housing off and shorting it out. wasn't my first thought, bc/ FP and CE was coming on, then realized that it was only the voltage supply wire, the PCM would still get response form the CPS b/c there would still be resistance from the magnetic pull of the Flywheel. So first thinkg I checked fuel injectors for voltage whiel cranking and nothing, so then I reached back and got the CPS wiring and pulled it up (trying to look for bad spot which was a pain in the ass couldn't see shit) and decided well it should be fine now since it isn't touching anythign metal and checked my voltage again with the jumper hooked up and had voltage - holy crap, checked voltage at the Cam Sensor and had voltage, so hooked everything back up, rechecked voltage at cam sensor and still had voltage got in the jeep turned the key and she fire right up. PROBLEM SOLVED - I will have to go in and fix the CPS wire but it should be good til next weekend.
BLAH BLAH BLAH.
Got the jeeper runnin again, it was all caused by the CPS wire hitting the exhaust manifold and burning the housing off and shorting it out. wasn't my first thought, bc/ FP and CE was coming on, then realized that it was only the voltage supply wire, the PCM would still get response form the CPS b/c there would still be resistance from the magnetic pull of the Flywheel. So first thinkg I checked fuel injectors for voltage whiel cranking and nothing, so then I reached back and got the CPS wiring and pulled it up (trying to look for bad spot which was a pain in the ass couldn't see shit) and decided well it should be fine now since it isn't touching anythign metal and checked my voltage again with the jumper hooked up and had voltage - holy crap, checked voltage at the Cam Sensor and had voltage, so hooked everything back up, rechecked voltage at cam sensor and still had voltage got in the jeep turned the key and she fire right up. PROBLEM SOLVED - I will have to go in and fix the CPS wire but it should be good til next weekend.
talbritton
09-20-2005, 11:19 AM
seems that i'm having the same type issues w/ my 96 jgc also but my fuse-link from the alt to the pdc is starting to fry/melt. new plugs;wires;cap;rotor; asd relay;#20-20amp fuse; and on my fifth coil? lost in the electrical matrix please help!!!
89ltd
09-21-2005, 07:09 AM
what size engine do you guys have???
talbritton
09-23-2005, 12:06 PM
6 cyl 4.0 Litre
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