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1998 Jeep Cherokee has ignition system problem.

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Old Apr 19, 2009 | 03:02 PM
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Default 1998 Jeep Cherokee has ignition system problem.

So i have a 98 Cherokee, that much you know. Not long ago the check engine light came on while i was driving so i went to an Autozone and had them check the code. They said the code was from the CamShaft position sensor. Theres only one problem. I have a 98 and my Haynes manual only lists a Cam Pos Sensor for 2000 or newer cherokee's.

but even then it was running fine.

now it wont start. I getting what i think is good fuel pressure across the fuel bar (30- 40 psi).

i checked the spark and its not sending a spark past the ignition coil, but the coil isnt bad. I checked the input voltage and i have voltage coming into the ignition coil. so on the random chance the coil was bad i went and picked one up and installed it. Still no spark. so i need some help.

Something is preventing the coil from sparkin my plugs.
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Old Apr 19, 2009 | 04:05 PM
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no spark ok good lead. does it have a signal to the injectors? if not thats the crank sensor located on the top of the bellhousing on the driverside. It's pretty common.
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Old Apr 19, 2009 | 04:51 PM
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how do i check for a signal to the injectors?

I have a Fluke meter and im pretty good with electronics, but i dont want to cost myself more money because i did something stupid.
And if i find that i dont have a signal, how do i check the crank sensor to see if its faulty or not
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Old Apr 19, 2009 | 05:01 PM
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ive never had to mess with a CPS sensor but id imagine it's a magnetic swith open/closed by the turning of the flywheel. It should be able to be checked while cranking with a OHM meter. Some one will correct me if im wrong......
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Old Apr 19, 2009 | 05:37 PM
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You have a cam sensor... the distributor.
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Old Apr 19, 2009 | 05:50 PM
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the distributor is not bad

the problem is before the ignition coil somewhere. And i was refereing to a specific part called a Cam Position sensor. But thanks for trying.
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Old Apr 19, 2009 | 05:56 PM
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you can do a real quick test to see if the injectors are working with some common stuff around the house i homemade a noid light using a xmas tree light bulb. i pulled it out of the plastic holder straightened out the wires on the light and solderd on longer wires then i simply removed the connector to the fuel injector and touched the wires to the terminals on the connector and have a buddy crank it over you should see the bulb flash rapidly if your getting signal
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Old Apr 19, 2009 | 05:57 PM
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i would say its probably your crank sensor.
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Old Apr 19, 2009 | 06:13 PM
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Originally Posted by Sublime
the distributor is not bad

the problem is before the ignition coil somewhere. And i was refereing to a specific part called a Cam Position sensor. But thanks for trying.

The cam sensor is in the bottom of the distributor... below the rotor. It's a Hall-effect device that is way before the coil. The cam sensor tells the PCM where #1 cylinder is.

It looks like this:



EDIT: I'm not saying this is the problem. I'm trying to help you understand how it works.

Last edited by solderjunkie; Apr 19, 2009 at 06:29 PM.
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Old Apr 20, 2009 | 06:16 PM
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yea you can use a fluke meter on it. just hook it up and have a buddy crank it while you test it
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Old Apr 20, 2009 | 06:19 PM
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Originally Posted by Sublime
how do i check for a signal to the injectors?

I have a Fluke meter and im pretty good with electronics, but i dont want to cost myself more money because i did something stupid.
And if i find that i dont have a signal, how do i check the crank sensor to see if its faulty or not
you can get noid lights from a auto parts store their pretty cheap. just plug it into the the connector to the injector and crank it and see if you got a pulse
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Old Aug 14, 2010 | 07:29 PM
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hey i currently have the same problem. but i did something to do this. but how do you pull and test the cam position sensor...
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Old Aug 17, 2010 | 05:34 PM
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I have a 98 also and the CPS is what i had to replace. good diagram by the way.... would have been good info before i bought a coil that did not fix the problem. the Cam Position Sensor is a cheaper and WAY easier part to replace than the Crank Position Sensor
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Old Aug 28, 2011 | 11:11 AM
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have a problem on my 98 with no spark getting to the coil. replaced the coil and it started and ran fine that same night. let it sit for three days and now no spark to the coil again.
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Old Aug 28, 2011 | 12:59 PM
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Crank position sensor on top of the bell housing. Causes issues as described.

Flash
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