cruiser54 Posted July 29, 2014 Share Posted July 29, 2014 I had a weird issue on my 88 XJ where the internal ground wire from the pump to the mounting flange got hot due to a loose connection and would cause a cut-out and stall. Here's a thought also. There's a ground for the fuel pump behind the driver's side taillamp......... Link to comment Share on other sites More sharing options...
Jaime Posted August 6, 2014 Author Share Posted August 6, 2014 Hello again, Well my truck still keeps shutting off. I have been noticing that it tends to shut off during acceleration. If I'm at a light and I take off, I get about 10 feet then it shuts off. Sometimes I can just put it in neutral and it will come back on after a moment or two. Other times I have to cycle the key. It happens in 3rd or 4th as well. I went thru all the grounds again thinking that I missed something. While at the back light ground I decided to pull back the plastic covering and I discovered a common connection for the ground, about 5 inches back, crimped together. It looks like a factory crimp to me and does not look corroded. I tried to post a picture of the connection but it won't take. I think this weekend I am going to buy a soldering iron and solder that connection or should I leave it alone? I also want to drop the tank and check the connection like cruiser said. Can I get any suggestion as to what else to test, sensors and how to check them, other hidden grounds. Getting tired of getting flipped off because they think I'm brake checking them. Link to comment Share on other sites More sharing options...
cruiser54 Posted August 6, 2014 Share Posted August 6, 2014 Never a bad idea to improve grounds by any means possible, including soldering. Link to comment Share on other sites More sharing options...
BeenJaminJames Posted August 6, 2014 Share Posted August 6, 2014 In most (not all) cases, backfires into the intake are caused by a lean condition, and backfires out the exhaust are caused by a rich or intermittent-spark condition. Cutting out at random, and then backfiring out the exhaust is a classic sign of ignition issues. Step #4 in Cruisers renix tips shows how to clean the coil/ICM contacts. If you haven't done so already, I'd make that the next thing on the list to take care of. Another issue could be the stator putting out a weak signal. You can find a good write-up on how to test it here. Be sure to use an analog meter when you do the test. Link to comment Share on other sites More sharing options...
cruiser54 Posted August 7, 2014 Share Posted August 7, 2014 In most (not all) cases, backfires into the intake are caused by a lean condition, and backfires out the exhaust are caused by a rich or intermittent-spark condition. Cutting out at random, and then backfiring out the exhaust is a classic sign of ignition issues. Step #4 in Cruisers renix tips shows how to clean the coil/ICM contacts. If you haven't done so already, I'd make that the next thing on the list to take care of. Another issue could be the stator putting out a weak signal. You can find a good write-up on how to test it here. Be sure to use an analog meter when you do the test. Just unplug the stator and see how it runs. Link to comment Share on other sites More sharing options...
95wrangler Posted August 7, 2014 Share Posted August 7, 2014 bad coil? Link to comment Share on other sites More sharing options...
Jaime Posted August 7, 2014 Author Share Posted August 7, 2014 Actually it has not backfired for awhile now; and the more I think about it, I may have been causing the backfiring because I was putting in a lower gear. It was shutting off at the worst possible time (in the middle of rush hour). So in a panic to get it started or out of the way of traffic, I would put it in a lower gear. Since then, I just take it out of gear and coast to the side of the road. It hasn't backfired since. Link to comment Share on other sites More sharing options...
cruiser54 Posted August 7, 2014 Share Posted August 7, 2014 So give us a re-cap please of what you did so far. And, the problems are gone? Link to comment Share on other sites More sharing options...
BeenJaminJames Posted August 7, 2014 Share Posted August 7, 2014 Just unplug the stator and see how it runs. I'm still learning the idiosynchracies of the renix electronics.... So in the absence of a signal from the stator, doe the ecu signal the icm from the cps signal? Other engines I have experience with all relied on the stator alone to directly fire the ignitor, independent of any signal from the ecu. Unplugging the stator on these vehicles would simply disable the entire ignition system Link to comment Share on other sites More sharing options...
Minuit Posted August 7, 2014 Share Posted August 7, 2014 I had a similar issue with random shut-offs. Mine never backfired but it always seemed to start right up after cycling the key. I replaced the ignition coil and it never did it again. Link to comment Share on other sites More sharing options...
cruiser54 Posted August 7, 2014 Share Posted August 7, 2014 Just unplug the stator and see how it runs. I'm still learning the idiosynchracies of the renix electronics.... So in the absence of a signal from the stator, doe the ecu signal the icm from the cps signal? Other engines I have experience with all relied on the stator alone to directly fire the ignitor, independent of any signal from the ecu. Unplugging the stator on these vehicles would simply disable the entire ignition system The stator has NOTHING to do with ignition. That's controlled by the ECU via CPS and some other inputs. The stator only controls the sequential firing of the injectors. Unplug one on a renix and see if you notice a difference in performance/running. Link to comment Share on other sites More sharing options...
shelbyluvv Posted August 7, 2014 Share Posted August 7, 2014 I know my truck is a 97 converted HO but I have a similar issue. I know for a fact mine is the ignition switch. If I hang a key ring from it, it will jiggle the tumbler just enough the shut it off. I need to adjust the switch but I am lazy. It is a long shot but it is possible yours could be doing the same. Link to comment Share on other sites More sharing options...
Jaime Posted August 8, 2014 Author Share Posted August 8, 2014 I did steps 1 thru 5 of your tips. When it started, it would shut off in the morning after about 2 miles down the road. In a panic to get out of the way, I would put it in a lower gear and pop the clutch. Then it would back fire. It happened enough times, that my muffler split. After that, it started shutting off on the way home from work and only about 3/4 of a mile down the road. I did your tips, but it still keeps shutting off. Then it started not wanting to start as normal. It would crank; but not start, and a couple of times white smoke came out of the breather box. Fortunately, that has not happened anymore. The back firing has also stopped since I stopped popping the clutch. What I do now is push the clutch in or take it out of gear. Sometimes it starts after 2 to 3 seconds. Other times I have to cycle the key. The truck runs smooth before and after it shuts down. It almost feels like it is running out of gas at times. I have also changed the fuel filter and gone thru the grounds a second time just to be sure. That is when I discovered that about 3 to 4 wires connect to the ground wire going behind the taillight. Things I plan on doing this weekend is to solder the crimp at the taillight and the c101 connection. Hopefully, I will also be able to drop the tank and check the wire connection that you were talking about. I was actually thinking of replacing the ignition switch if nothing else worked, because I also discovered that I can take the key out of the ignition and the truck will continue to run. As for the coil, can I test it before I change it? I need to buy a soldering iron. What wattage do you recommend? Should it be an iron or a gun? I want to thank all of you for your inputs so far as I would not even know where to begin without them. Thanks! Link to comment Share on other sites More sharing options...
cruiser54 Posted August 8, 2014 Share Posted August 8, 2014 Good old soldering gun with 2 settings depending on he trigger pul is great. Nothing fancy. Link to comment Share on other sites More sharing options...
Jeep Driver Posted August 8, 2014 Share Posted August 8, 2014 I've gone through several of the pencil type soldering irons and they just do not last, even the Wellers don't. The old fashion Weller gun is what I have now. Link to comment Share on other sites More sharing options...
Jaime Posted August 11, 2014 Author Share Posted August 11, 2014 Well I eliminated the C101 connection and the factory crimp (or I think it was the factory crimp, I'm not sure) that has 8 wires going to it behind the taillight. I was left with 4 wires on the C101 connection that did not have corresponding wires on the other side of the connecter. Since I don't have an A/C, I am assuming that these wires are for the A/C. These are the colors of the wires I'm talking about: red, gray w/black tracer, and tan w/orange tracer coming from the engine side of the connector. The firewall side is blue w/white tracer. I went for a ride in it, about 30 miles, without it shutting off on me. I'll see what happens this week and let you know. Link to comment Share on other sites More sharing options...
88whitemanche Posted August 11, 2014 Share Posted August 11, 2014 Those extra lines are for the connector for an automatic transmission....just tape off the ends and your good.... I was having this same issue after upgrading that rear taillight factory crimp...my truck has been running flawlessly that past 100+ miles.... Link to comment Share on other sites More sharing options...
Jaime Posted August 13, 2014 Author Share Posted August 13, 2014 Hello everyone, The truck turned off on me twice today. In the morning I was almost to work about 7 miles. As I turned a corner it turned off, going from 1st to 2nd. It also shut off on the way home. This time I was at a stop light when it turned off. Both times I just cycled the key and the truck started. The rest of the trip was uneventful. I want to put a new coil and a new ignition switch in it as suggested but would like to preform a test on them before I buy them. Can someone let me know how to test them if possible. Thanks. Link to comment Share on other sites More sharing options...
cruiser54 Posted August 13, 2014 Share Posted August 13, 2014 Hello everyone, The truck turned off on me twice today. In the morning I was almost to work about 7 miles. As I turned a corner it turned off, going from 1st to 2nd. It also shut off on the way home. This time I was at a stop light when it turned off. Both times I just cycled the key and the truck started. The rest of the trip was uneventful. I want to put a new coil and a new ignition switch in it as suggested but would like to preform a test on them before I buy them. Can someone let me know how to test them if possible. Thanks. Intermittent stuff is hard to catch. What do your gauges do when it shuts off? Refresh me. Have you done the coil/ICM contacts? Link to comment Share on other sites More sharing options...
Jaime Posted August 13, 2014 Author Share Posted August 13, 2014 The tack goes to zero, temp stays at normal, and the oil goes to zero. I haven't seen what the volts gage does but I'll check it next time it shuts off. Yes I've done the coil/CM contacts, steps 1 thru 5 and step 27 of your tips along with the extra ground at the taillight that I found. I kind of wish that I had put a thicker wire on that ground. Link to comment Share on other sites More sharing options...
cruiser54 Posted August 13, 2014 Share Posted August 13, 2014 So, does it always start right back up, or do you have to wait for a period of time? Link to comment Share on other sites More sharing options...
Jaime Posted August 13, 2014 Author Share Posted August 13, 2014 It always starts right up and then run fine for the rest of the trip. Link to comment Share on other sites More sharing options...
cruiser54 Posted August 13, 2014 Share Posted August 13, 2014 No wait time? Why don't you at least take a gander at the ignition switch up under the dash on top of the steering column? Maybe it's crispy looking? So, the temp gauge stating normal points to the ignition switch working in the On position though. Tach dropping could be bad CPS or just the fact the engine died as well as the oil pressure reading. The fuel and voltmeter gauges should be checked immediately when this happens. Have you ever let it idle and performed a "wiggle test" of the various harnesses in the engine bay? Link to comment Share on other sites More sharing options...
Jaime Posted August 13, 2014 Author Share Posted August 13, 2014 I just took a peak at the ignition switch. It looks OK to me. I think I'll take it off this weekend to get a better look. I did the test you had me do on the CPS toward the beginning of the post and it tested OK. Yes on the wiggle test. I also slightly pulled, pushed and wiggled on all the connections I could find. Link to comment Share on other sites More sharing options...
cruiser54 Posted August 13, 2014 Share Posted August 13, 2014 Then it may be a thermal problem. Something gets warm and fails monentarily, cools off, and is then okay. How tight are the connectors on the fuel pump ballast resistor? Link to comment Share on other sites More sharing options...
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