1990 getting no spark

[mercadian31]

Ok i have one that may stump the best of the best that does not have a diagnostics machine. I have a 90 trooper with 5 spd and a 4 banger. it will not start. i have replaced the ingnition switch, coil, plugs, wires, distributor, cap, rotor bug, and a power supply relay that is located under the intake. This thing will not start what so ever. I have spent about $600 and about 15 hours going through each wire. if anyone has a clue about what this may be please email me at [email protected] or call at 918-636-1429. i have almost gone insane over this.
peace

[travelman]

Sorry I don't have a magic/psychic diagnosis for you. You need to give us some information on what the symptoms are other than won't start. Does it crank? Do you have spark? Is fuel being delivered? How did the problem start? Past problems? What do the plugs look like? The more information you give the more help you can get.

Also while you can try to do this offline do you really want to? Don't you want as many people as possible trying to help? Also solving your problems online now may help another person with similar issues later on.

[mercadian31]

Most deffinetly. I would love to help someone else besides myself. What i said, now looking over it, sounds kinda rude. i do apologise for my tone. Anyways, i am getting fuel, it will crank but not start. No spark at all. i have pulled the plugs and theres not even a little flicker of electricity. this has been going on for about a month and a half. the plugs are new and it doesn't have any prior probs. i bought it in oklahoma city, OK and drove it back to Tulsa, OK which is about 120 miles away. drove great. i drove it around tulsa the next two days and didn't have a prob. then i went to a friends house and parked. went in for about 1 1/2 hours, came out and then it wouldn't start. at first we thought it was the gas but we put over 5 gallons in it and it still didn't go. then we checked the oil and it was a little low but nothing to get bent over. then we tried to pop the clutch but that had the same effect. once i got it home i took off the gas tank and checked everything. the fuel pump lines injectors. all were good. then i fixed a leaky cam shaft gasket, but that did have any effect either. then i started replacing stuff, distributor, rortor bug, plug wires, plugs, cap, coil, power supply relay under the intake, fuses, and still nada. so that brings me up to now. i have nothing left and i have traced every wire that comes off the harness. i have taken the covers off of all the wiring harness and rewraped them to check for bad wires and nothing. any help that someone would be able to give me i would really be thankful.

[travelman]

It didn't come across to me as rude, just maybe frustrated as well you should be.

Many years ago the first time I checked for spark I pulled out the plug fired it up and no spark at the plug I was checking. In my case the other cylinders were firing and the engine running. Then I thought it through and realized I needed to ground the plug before it would conduct a spark. One jumper cable clipped to the plug base and frame later I determined I did have a spark. Not saying you oopsed like I did but just in case.

Given all you have done I am currently at a loss as to what is left. Kind of thinking/writing out loud here so bear with me. Some sort of interlock (clutch, AT not in park, or aftermarket alarm???) that won't let it start? Is it cranking, if so that would likely rule that out. Hidden relay? Something messed up during your earlier work (e.g. miswired coil wire?) but that seems unlikely. This is going nowhere fast. While waiting for better help you may want to get a voltmeter and start at the battery and head towards the sparak plug and see where you lose voltage.

[ActionVerb]

lets see..... no spark at the plug..... I'd start working back toward the battery from there, see if you can get ignition spark/juice anywhere. None at the plug, so check the plug wire, then the coil wire etc. Im not too familiar with how the battery power gets to the coil, but I believe there's a relay on the alternator that switches battery juice to the starter and coil when activated. Also Ive found and bad coil wire once by swapping it with a plug wire. good luck

chris

[javatrooper]

Does your distributor spin when engine cranked? just a thought. You need a voltmeter and then check for current. turn on your ignition key and see if you have voltage at your coil, dist, etc. The current must stop somewhere between your battery and your plugs. you just have to trace it back. easier said than done, but you must be missing something. Is there any corrosion where the ignition system hooks up to the battery? good luck.