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Not getting a spark?!?!

TexasCherokee4x4

NAXJA Forum User
Location
San Antonio, Tx
Okay here's the break down. Just replaced the motor. Now I got it all put back together, but I'm not getting spark at the plugs. I have a brand new ignition coil and ignition control module, new spark plug wires and spark plugs, and I have a new distributor cap and rotor. The battery is brand new and it will rotate the motor it just won't fire up. I don't know what to do. I seem to have exhausted all my answers. Thanks for the help guys.

Robert
 
Check your CPS output to verify it's condition.

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 it’s mounting holes with the first drill bit that just won’t fit through the original holes. Then, when mounting it, hold the CPS down as close to the flywheel as you can while tightening the bolts.
 
Revised 11-29-2011
 
Please confirm what year it is?

Did the CPS get damaged during the engine swap? Or any damaged wires, wiring harness damage? Anything you forgot to re-connect?
 
Very common to have damaged crankshaft position sensor wiring after an engine swap. Or forget to connect it.

Good advice above. You must verify crank sensor circuit is working properly. You will have no spark and you won't have fuel going to the injectors if there is an issue with it.
 
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