wombat Posted November 23, 2014 Share Posted November 23, 2014 Yesterday I bought an 86 comanche, 2wd 2.5 4 speed. PO said that it lost pulse at the injector. He replaced the injector, and fuel pump but didn't go anyfurther. Got it home and got to look at it for a min this evening. it won't hit on starting fluid, so I put a spark tester on it. Nothing. I have no pulse, and no fire... his back story was, it died on him. he let is sit 15 mins, was able to start it and get home. turned it off, and it never started again. Anyone have a starting point for me? Link to comment Share on other sites More sharing options...
HOrnbrod Posted November 23, 2014 Share Posted November 23, 2014 Ignition coil. Link to comment Share on other sites More sharing options...
wombat Posted November 23, 2014 Author Share Posted November 23, 2014 would that have anything to do with the injector not pulsing? its an obvious that the coil can be suspect for the no spark..... just didn't know if there was anyway to check it without replacing it? or if there was something else to look at first that could cause loss of both? Link to comment Share on other sites More sharing options...
Jeep Driver Posted November 23, 2014 Share Posted November 23, 2014 Could be CPS Link to comment Share on other sites More sharing options...
wombat Posted November 23, 2014 Author Share Posted November 23, 2014 no way to test without replacing though, and I'm not in a position to throw parts at this thing. Link to comment Share on other sites More sharing options...
wombat Posted November 23, 2014 Author Share Posted November 23, 2014 I am a compitent mechanic, just trying to see if there is anything specific on these that is common to cause these symptoms.. I haven't really had a chance to look at it much yet. Link to comment Share on other sites More sharing options...
88whitemanche Posted November 23, 2014 Share Posted November 23, 2014 Ok start with cruisers renix tips... All of these will help you diagnose your no start and help improve your truck.... http://comancheclub.com/topic/36382-cruisers-renix-tips/ Link to comment Share on other sites More sharing options...
benjy_26 Posted November 23, 2014 Share Posted November 23, 2014 From what I understand, 2 things (that *I* know of) that could cause a no spark/no pulse issue us the CPS and the pickup coil. You tested the injector pulse with a noid light, right? Link to comment Share on other sites More sharing options...
dasbulliwagen Posted November 23, 2014 Share Posted November 23, 2014 This is a TBI. Not sure they make a noid for that style injector Link to comment Share on other sites More sharing options...
benjy_26 Posted November 23, 2014 Share Posted November 23, 2014 A bit of scrap wire and a few minutes can get a noid working on that bad boy. ;) Link to comment Share on other sites More sharing options...
cruiser54 Posted November 23, 2014 Share Posted November 23, 2014 no way to test without replacing though, and I'm not in a position to throw parts at this thing. Oh, yes there is a way to test the 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 Link to comment Share on other sites More sharing options...
wombat Posted November 23, 2014 Author Share Posted November 23, 2014 you guys are awesome, thanks for the tips, I'll check into them. Link to comment Share on other sites More sharing options...
Eagle Posted November 23, 2014 Share Posted November 23, 2014 Could be CPS I think we have a winner. Link to comment Share on other sites More sharing options...
wombat Posted November 23, 2014 Author Share Posted November 23, 2014 I just pulled the CPS off and it did have alot of material on it... The PO did tell me the clutch was starting to slip, that makes since. He did give me a brand new clutch with it though. Link to comment Share on other sites More sharing options...
wombat Posted November 23, 2014 Author Share Posted November 23, 2014 if the cps was bad would it also kill my injector pulse as well as the spark? Link to comment Share on other sites More sharing options...
ComancheKid45 Posted November 23, 2014 Share Posted November 23, 2014 Yes it could. Link to comment Share on other sites More sharing options...
wombat Posted November 23, 2014 Author Share Posted November 23, 2014 ok got the CPS back in. no difference. Witch wire going to the coil could I check to make sure its getting power to it? Link to comment Share on other sites More sharing options...
wombat Posted November 23, 2014 Author Share Posted November 23, 2014 just realized that the ignition switch is touchy. when in the ON position i have to wiggle the key to get the buzzer to come on. another possible culprit... I also can't here or tell if the fuel pump is kicking on. The PO did say that he had it checked, and that it was good. Link to comment Share on other sites More sharing options...
Jeep Driver Posted November 24, 2014 Share Posted November 24, 2014 ok got the CPS back in. no difference. Witch wire going to the coil could I check to make sure its getting power to it? Did you test it? or replace it? Link to comment Share on other sites More sharing options...
wombat Posted November 24, 2014 Author Share Posted November 24, 2014 niether. just cleaned it. I gotta bring my multi meter home from work tomorrow. Link to comment Share on other sites More sharing options...
wombat Posted November 24, 2014 Author Share Posted November 24, 2014 Tested the CPS tonight..... 3.1AC. I'll be picking one up as soon as I can this week. wish me luck and thanks for all the help guys. Any suggestion on wich brand? Link to comment Share on other sites More sharing options...
Jeep Driver Posted November 24, 2014 Share Posted November 24, 2014 I try to stay away from BWD Link to comment Share on other sites More sharing options...
wombat Posted November 24, 2014 Author Share Posted November 24, 2014 I was looking at Rock auto. The only 2 brands they list are airtex, and standard something or another. Link to comment Share on other sites More sharing options...
Jeep Driver Posted November 25, 2014 Share Posted November 25, 2014 NAPA http://www.napaonline.com/Catalog/CatalogItemDetail.aspx/Crankshaft-Sensor/_/R-ECHCSS980_0336127758 or the Standard Motor Products brand is good. Link to comment Share on other sites More sharing options...
wombat Posted November 25, 2014 Author Share Posted November 25, 2014 thanks man' Link to comment Share on other sites More sharing options...
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