Siever_93

Okay guys so I did a swap from a HO 4.0 back to a Renix 4.0 I got everything hooked up and its sitting in the jeep but I dont have spark, I noticied my Cps wires were pretty ugly looking but it worked on the original motor, Im going to replace it along with a new battery, But what else could be the cause? Im in the dark right now

odgreen

What flywheel/flex plate you use. You can't use the ho flex plate on the renix system.

xjmarc

What did you do about the knock sensor cause Renix has one and the HO doesn't?

Jeepcherokee123

Ground strap from firewall to head ?

odgreen

There is still a place to screw it on the block.

And missing it wouldn't cause it not to start.... I was missing mine when I got it.

cruiser54

Knock sensor is not required on the HO. Don't install it. No place to plug it into the HO harness anyway.

The flexplate used needs to be addressed first.

Jeepcherokee123

I think he is going from HO to RENIX

cruiser54

He is. So, he uses all the electronics off the HO on the REnix. The HO electronics do not include a knock sensor.

Siever_93

Sorry for the late replies guys, I took a ho and used the renix birds nest wireing system, Yes i did install the knock sensor along with the coolant temp sensor and the renix flexplate and yes the engine is grounded by the ground strap. The only thing I can think is that the cps is bad, that or I installed the distributor wrong but even if I was off timing with the dist wouldnt it still get spark?

scheetz_21

Fuses! Have had it happen before! Check them first to be safe.. Coil ohm out good? Then check pick up coil..

cruiser54

There are no fuses on the Renix system to cause a no-start. They have no pick-up coil either.

cruiser54

Now this is a bit more clear. What year chassis are you using?

Here's how to check a Renix CPS output.

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, 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 07-30-2012

Siever_93

Thank you, you dont know how much it means for you help. But would I still have spark if I had my distributor timed incorrectly?

cruiser54

Yes. You would have spark, just at the wrong time. Think you got the distributor in wrong?

twistedunibody01

Correct me if I'm wrong but I over heard someone say the distributor can only go in 2 ways, the right way are completely 180% the wrong way. That may help if it's the correct information