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Unread 06-06-2013, 06:44 PM   #16
Bryce527
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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.

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Unread 06-06-2013, 10:43 PM   #17
cruiser54
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Quote:
Originally Posted by Bryce527 View Post
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.
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.
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If you own a Renix Jeep, you'll want to check this out. >

An index to over 25 write-ups can be found in Post #1.

Cruiser's Mostly Renix Tips
My Jeep Technical Photos

http://www.cherokeeforum.com/g/album/1725214
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Unread 06-12-2013, 08:33 AM   #18
Bryce527
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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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Unread 06-12-2013, 10:26 AM   #19
Speedymcracer01
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Its just going bad. The magnet might have metal shavings and gunk on the end of it though. Have you took it out and tried cleaning it? Other than that i would go get a replacement for around $40
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Unread 06-12-2013, 10:36 AM   #20
Bryce527
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Yeah before I purchased the new one I cleaned off the old one pretty well and tried it again. And alrighty thanks!
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Unread 06-12-2013, 10:47 AM   #21
Speedymcracer01
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Any time
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Unread 06-12-2013, 04:25 PM   #22
cruiser54
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Do the mod in the write-up below.

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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Quote:
Originally Posted by chris87xj View Post
If you own a Renix Jeep, you'll want to check this out. >

An index to over 25 write-ups can be found in Post #1.

Cruiser's Mostly Renix Tips
My Jeep Technical Photos

http://www.cherokeeforum.com/g/album/1725214
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Unread 06-13-2013, 09:21 PM   #23
Bryce527
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Okay so my CPS is putting out around .45 now and still no start. I'm not getting spark at the plugs nor at the coil. But I am getting a constant voltage at the coil. Would it be the coil has gone bad even though I still have around 12volts going through but nothing more for a spark? Or what tells the coil to create the spark?
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Unread 06-13-2013, 09:41 PM   #24
cruiser54
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Renix Jeep ICU/Coil contact refreshing



The contacts between the coil and the ICU on your Renix Jeep can become corroded and loose causing a complete or intermittent no-start condition. I recommend the following procedure as a maintenance precaution to insure this is eliminated as a possible cause now and in the future.

The coil is attached to the ICU by two T20 Torx bolts. Remove these two bolts and lift the coil up off the ICU. You will see 2 pins and 2 sets of contacts. Clean both the pins and springy contact pieces with a good electronics cleaner and some fine sandpaper.
Squeeze the springy contacts closer together with some needlenose pliers. Bolt the coil back on to the ICU.
While you’re right there, unplug the connectors from the ICU and inspect the pins in the harness connector. Make sure the pins are not retracted into the connector. Spray out the connector and the receptacle of the ICU with the same good electronics cleaner you used earlier.
I feel this procedure should be performed at least once in the lifetime of a Renix Jeep.


Revised 04-04-2013
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Quote:
Originally Posted by chris87xj View Post
If you own a Renix Jeep, you'll want to check this out. >

An index to over 25 write-ups can be found in Post #1.

Cruiser's Mostly Renix Tips
My Jeep Technical Photos

http://www.cherokeeforum.com/g/album/1725214
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Unread 06-21-2013, 09:18 AM   #25
gs69350
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Take distributor cap off and make sure the rotor is spinning when the engine is cranking.
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Unread 06-21-2013, 10:58 PM   #26
Bryce527
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Thank you so much for all the feed back. I got it running this week. The engine has started but it's running rough. It runs rough ad shakes at idle but if I give it a little gas it smooths out. I'm guessing that it's because the distributor isn't seated correctly. Not being a very skilled mechanic I can't seem to get it in place correctly. Can someone help explain the process of getting in correct? Or maybe these symptoms are not due to the distributor being placed incorrectly? I've tried seating maybe a dozen times. I've read and done it many ways through a Haynes manual and places online
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Unread 06-22-2013, 06:25 AM   #27
cruiser54
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First, need to do this:

Setting Your 4.0 at #1 TDC


With #1 spark plug removed, turn the engine over clockwise using the 3/4" front crankshaft bolt. You will see the degree marks on your front cover. Mark the 0 with chalk or white-out.You will see the timing mark on the balancer. Mark it with chalk or white-out. While turning the engine over, put your finger/thumb over #1 spark plug hole. As the mark on the balancer approaches the marks on the front cover, if you are coming up on #1 TDC, pressure in the cylinder will push on your finger. If there's no pressure, you're at #6 TDC and need to crank the engine over until you see the marks coming together and you get pressure. Set the mark on the balancer to the 0 mark on the front cover.


Then align the oil pump/distributor shaft per the manual.

To check the indexing, use this:




Remove the distributor cap and cut a "window" into the side of the distributor cap at the #1 spark plug wire post . The "window" should be large enough to allow easy visual inspection of the position of the distributor rotor at the #1 spark plug wire post. Reinstall the distributor cap.

Install a wrench or socket onto the vibration damper retaining bolt. Rotate the engine in a clockwise direction until the #1 cylinder is at top dead center. Align the timing mark on the vibration damper with the "0" degree mark on the front cover timing scale. The tip of the distributor rotor should be near the #1 spark plug wire post.

Disconnect the distributor electrical connection. Remove the distributor holddown clamp, holddown bolt and distributor. Remove the distributor cap and rotor.

Place the distributor housing upside down in a soft jaw vise. Scribe a line 1/2 inch from the end of the distributor locating tab. Cut the distributor locating tab at the scribed line with a saw.

Remove any burrs and metal filings from the distributor. Reinstall rotor.

If necessary, using a flat blade screwdriver, turn the oil pump gear drive shaft until the slot is slightly past the 11 o'clock position. The oil pump gear drive shaft is accessible through the distributor mounting bore in the engine block.

Visually align the modified locating tab area of the distributor housing with the holddown clamp bolt hole.

Turn the rotor to the 4 o'clock position.
Lower the distributor into the engine block until it seats. The rotor should now be very close to the 5 o'clock position.

Reinstall the distributor cap with the cutout "window". Rotate the distributor housing until the trailing edge of the distributor rotor tip is just departing from the #1 spark plug wire post terminal .

Reinstall the distributor holddown clamp and bolt.. Reinspect the position of the rotor to the #1 spark plug wire post to insure that it has not moved.

Install the new distributor cap, reconnect the distributor electrical connections.

Revised 07/03/2012
renix-dizzy-indexing.jpg  
__________________
Quote:
Originally Posted by chris87xj View Post
If you own a Renix Jeep, you'll want to check this out. >

An index to over 25 write-ups can be found in Post #1.

Cruiser's Mostly Renix Tips
My Jeep Technical Photos

http://www.cherokeeforum.com/g/album/1725214
cruiser54 is offline   Reply With Quote Quick reply to this message
Unread 06-22-2013, 06:34 AM   #28
Bryce527
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Join Date: Jun 2013
Location: , VA
Posts: 17
I have the 2.5l 4-cylinder but I'm guessing that is a similar process? Also I have one question. What's the vibration damper and what is the balancer? What's the difference?
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comanche , engine , mj , problem , start

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