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Comanche won't start

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comanche engine mj problem start
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Bryce527

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Discussion starter · #1 ·
Okay so I have an 88 Comanche with the 2.5L engine. The thing will crank but just won't start. I'm having trouble figuring out what the issue is. And to be clear I am very unexperienced with working on cars.

Anyways. I have purchased a brand new battery for it. I have checked what is getting voltage. When it's trying to start there is electricity going from the ignition coil to the distributor but there isn't any coming from the distributor to the spark plugs. One would assume I guess that the distributor has gone bad, and that could be a possibility. As i dont know much about cars What else could be the culprit of this problem? Through research I've found maybe that the crankshaft position sensor has gone bad, or does this have nothing to do with it? What could cause the problem of power not coming from the distributor? If the distributor has not been properly installed would this problem happen? Or is the problem something that I have not mentioned?
 
Discussion starter · #3 ·
I apologize for a not very descriptive explanation. I have checked that there is 12volts coming from the coil to the center of the distributor but when cranked no spark is going to the distributor. Nor is there anything coming out of the distributor. I'm really not good with cars and apologize for my ignorance. I don't have much knowledge to know what could be cause of it not starting.
 
#4 ·
Bryce527 said:
I apologize for a not very descriptive explanation. I have checked that there is 12volts coming from the coil to the center of the distributor but when cranked no spark is going to the distributor. Nor is there anything coming out of the distributor. I'm really not good with cars and apologize for my ignorance. I don't have much knowledge to know what could be cause of it not starting.
Click to expand...
Sounds like you need to pull your distributor cap and check the inside for wear.i would also check the distributor the gears on the bottom could be worn have you looked to see if the rotary button inside the distributor is rotating like it should?
 
Discussion starter · #5 ·
I have looked inside the distributor cap and there's a possibility that it could wore down. Tomorrow I plan to go a head a get a cap and rotor and see if that fixes it. There are fairly cheap parts. The rotor is rotating when I crank the engine
 
#8 ·
Renix CPS Testing and Adjusting



Renix CPSs have to put out a strong enough signal to the ECU so that it will provide spark.

Most tests for the CPS suggest checking it for an ohms value. This is unreliable and can cause some wasted time and aggravation in your diagnosis of a no-start issue as the CPS will test good when in fact it is bad.

The problem with the ohms test is you can have the correct amount of resistance through the CPS but it isn’t generating enough voltage to trigger the ECU to provide spark.

Unplug the harness connector from the CPS. Using your voltmeter set on AC volts and probing both wires in the connector going to the CPS, crank the engine over. It won’t start with the CPS disconnected.

You should get a reading of .5 AC volts.

If you are down in the .35 AC volts range or lower on your meter reading, you can have intermittent crank/no-start conditions from your Renix Jeep. Some NEW CPSs (from the big box parts stores) have registered only .2 AC volts while reading the proper resistance!! That’s a definite no-start condition. Best to buy your CPS from Napa or the dealer.

Sometimes on a manual transmission equipped Renix Jeep there is an accumulation of debris on the tip of the CPS. It’s worn off clutch material and since the CPS is a magnet, the metal sticks to the tip of the CPS causing a reduced voltage signal. You MAY get by with cleaning the tip of the CPS off.

A little trick for increasing the output of your CPS is to drill out the upper mounting hole to 3/8” from the stock 5/16”, or slot it so the CPS bracket rests on the bell housing when pushed down. Then, when mounting it, hold the CPS down as close to the flywheel as you can while tightening the bolts.




Revised 01-26-2013
 

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Discussion starter · #10 ·
Okay replaced the crankshaft position sensor. Still not starting. I'm guessing it is some electrical or computer problem? What else could it be?
 
Discussion starter · #14 ·
Im going to do a lot of testing this weekend to try and pin point what it is. Ill test the CPS like in the above post. But What do you mean another CPS plug ?
 
#15 ·
There was a service bulletin to run a new harness right to the ECU for the cPS. After it was done, the tech was to cut off the old plug. They didn't always do it and so guys have replaced their cPS and plugged it into the dead harness plug which should have been snipped off. A bit of a long shot, but worth the 30 seconds to have a gander.
 
Discussion starter · #16 ·
Oh okay. I'll take a look at that then as with running tests this weekend. Thanks for all the help. I hope none of it's a lost cause. My aunt is who gave it to me but her boyfriend supposedly tampered with a lot of the wiring so I hope it's not worse than I think.
 
#17 ·
Bryce527 said:
Oh okay. I'll take a look at that then as with running tests this weekend. Thanks for all the help. I hope none of it's a lost cause. My aunt is who gave it to me but her boyfriend supposedly tampered with a lot of the wiring so I hope it's not worse than I think.
Click to expand...
The stuff in the write-ups is NEVER a waste of time and usually gives a beneficial result. Get to work on it and report back.
 
Discussion starter · #18 ·
Okay so I have tested the newly CPS and I got a reading around .25 and .35. From what it says that is not enough correct? I installed the old one to see what it would read and it was barely reading any voltage is that possible? I guess from it wearing down?

Where could I get a good CPS to put out the .5 volts that I need? Maybe the CPS is the problem.
 
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