renix no start, no spark
08-28-2013, 12:33 PM
#1
Senior Member
Thread Starter
Join Date: Dec 2011
Posts: 597
Likes: 0
Received 0 Likes
on
0 Posts
Model: Cherokee
renix no start, no spark
Was driving last night and the jeep died, then restarted, then died and wouldnt start.
Im getting 12v power to the distributer and to the icm but no spark at all where do I start
Im getting 12v power to the distributer and to the icm but no spark at all where do I start
08-28-2013, 04:34 PM
#3
::CF Moderator::
Join Date: Aug 2011
Location: Prescott, Az
Posts: 43,875
Received 1,526 Likes
on
1,238 Posts
Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
FYI, you can unplug that distributor plug on a rEnix and it will run...
Test the CPS. Here's how:
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
Test the CPS. Here's how:
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
Thread
Thread Starter
Forum
Replies
Last Post
Tj Cope
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
21
11-16-2022 08:32 PM
Blackcherokee290
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
27
07-26-2022 07:52 PM
Jose Calderon
Stock Grand Cherokee Tech. All ZJ/WJ/WK Non-modified/stock questions go here!
17
09-17-2015 08:57 PM
Tj Cope
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
2
08-22-2015 12:51 PM
Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)