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no spark from coil

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Old Jan 4, 2015 | 07:02 PM
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Default no spark from coil

i got a 1989 cherokee 4.0 no spark from coil new coil new cps tested icm good tested wires going into icm and only 1 yellow wire is has power traced othere yellow wire to ecm so put a new one in and still nothing any ideals what could be the problem also have a relay buzzing put new on in and still buzzing
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Old Jan 4, 2015 | 09:22 PM
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I'd like to help, but your post makes no sense since it has no punctuation.
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Old Jan 4, 2015 | 09:24 PM
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Originally Posted by cruiser54
I'd like to help, but your post makes no sense since it has no punctuation.
Do they even teach English in schools anymore?
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Old Jan 4, 2015 | 09:34 PM
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Originally Posted by Bustedback
Do they even teach English in schools anymore?
I think it's a cross between texting and Ebonics.
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Old Jan 4, 2015 | 09:45 PM
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i am not geting any spark from the coil and theres 2 yellow wire that run into the ignition control module i test the wires and i got power to 1 wire but nothing from the othere wire so i traced the small yellow wire and it gose to the ecm so thought ecm was bad got a new one and still have no power at the small yellow wire. i thank the wire was called d13 on the ecm so im not sure what to look at or try now
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Old Jan 4, 2015 | 09:46 PM
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Have you tested your CPS?

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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Old Jan 4, 2015 | 10:17 PM
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i got new cps from autozone i will test it and see what it reads thanks for the tip
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Old Jan 4, 2015 | 10:18 PM
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Originally Posted by 89 2door xj
i got new cps from autozone i will test it and see what it reads thanks for the tip
Sometimes they're weak right outta the box.

Why not do Tips 1,3,4, and 5 in my Pink Link below while you're at it?
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Old Jan 4, 2015 | 10:26 PM
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ill take at look at it all thanks for the help
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Old Jan 18, 2015 | 07:32 AM
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i also have a relay clicking/buzzing. found out theres no power to the distributor wireing still no spark from coil. could this be from a bad distributor or like auto shut down?
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Old Jan 18, 2015 | 09:07 AM
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Originally Posted by 89 2door xj
i also have a relay clicking/buzzing. found out theres no power to the distributor wireing still no spark from coil. could this be from a bad distributor or like auto shut down?
A Renix will run with the distributor wiring, the little one on the side, disconnected.
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Old Jan 18, 2015 | 04:49 PM
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so your saying that it dont need power to the distributor to work? and you got any ideal on what could make a relay buzz?
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Old Jan 18, 2015 | 05:21 PM
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Originally Posted by cruiser54
A Renix will run with the distributor wiring, the little one on the side, disconnected.
I thought the ICM needed that 5 volt square wave signal from the ECM to make the ICM/coil work.
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Old Jan 18, 2015 | 05:21 PM
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Originally Posted by 89 2door xj
so your saying that it dont need power to the distributor to work? and you got any ideal on what could make a relay buzz?
What relay was it?
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Old Jan 18, 2015 | 08:48 PM
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Originally Posted by CCKen
I thought the ICM needed that 5 volt square wave signal from the ECM to make the ICM/coil work.
Maybe. But the dizzy only runs the injectors sequentially from the innards of the dizzy.
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