QuestionQUESTION: Hi Roland, Somehow I have lost the thread or at least the ability to send you more info. The car would run for 5 minutes and die and then has no spark. No codes other than battery disconnected. So it was 1,2...5,5. Any help would be appreciated. Coil is good. Brand new
ANSWER: Hi Tom,
You didn't describe where you were checking for spark. But if the coil is good, and there are no fault codes related to the crankshaft position sensor (code 11), then I would wonder about whether the rotor in the distributor is "opening" as it warms up or a crack in the distributor cap, or the wire from the coil to the distributor cap may be flakey. When you have lost spark: See if you have spark on the wire from the coil to the distributor cap by holing the tip of that wire near the block (after removing it from the cap), and if you do then I would believe the rotor or the distributor cap is faulty.
Roland
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QUESTION: Roland, That's the issue, no spark coming from the coil. The coil will spark once as the ground wire is removed, and then again each time the ground wire is removed manually. That is how I know it is a good coil. I have tested it with the coil wire and without the coil wire with a jumper laying close to a ground to cause an arc. No luck. Something, probably a pick up coil inside the distributor, a crank sensor or the computer itself is not allowing the coil ground to be broken when cranking. However once in a while with a cold engine, it will start and run fine for 5 minutes then die.
ANSWER: Hi Tom,
If you have verified that you have no spark pulsing out of the spark coil wire while cranking over the engine, then I would suspect that the photo-optic sensing unit in the distributor is failing. It should produce a code 54 were that the case, but it may be marginal enough as to not set a code. Do you have a manual that shows how to service the distributor?
If you are getting sparking when cranking it over but you have no fault codes then I would suspect instead that the exhaust gas recirculation valve is gummed up and not closing tightly when you slow down to a stop. That also can prevent starting the engine when cold. You can lube the valve stem of the egr valve with WD-40 and the move it back and forth via the slot in the valve stem.
So verify whether or not you are getting spark pulsing when cranking it over to start with.
Roland
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QUESTION: No spark when cranking. It has a cycle. It starts and runs for five minutes then dies and has no spark at the coil. If I leave it alone for 5 or 6 hours it will start again and run for 5 minutes and die, at which point it will have no spark from the coil, and on and on. Today I tried something different.....Get this... I lit up the coil with a jumper from the battery positive to coil positive, all kinds of relays and fans came on and it started right up. I removed the jumper assuming it would die immediately and it did not die. It continued to run for over an hour until I shut it off with the key and now it starts and runs on demand and will stay running for as long as I want it to. I really want to know what happened.
AnswerHi Tom,
The coil positive wire you jumped 12v to is part of the "automatic shut down" system. Specifically, the engine controller is designed to provide 12v to the coil, the injectors, and heated oxygen sensors and the fuel pump. It does that by closing the automatic shut down relay initially for about 1 second when you turn the key to the run position, and then again when you try the starter and if the engine starts it continues to stay closed. If the engine shuts off then that relay is opened for the reasons of safety. I don't know why jumping 12v to the coil has solved the problem. The engine controller would have "seen" you do that but I don't know why that corrected the problem subsequently. Maybe the ASD relay is "flakey" is about the only explanation I can offer.
Roland
PS: Thanks for the rating and kind remarks. If you would care to also say "yes" to a nomination of me for volunteer of the month I would appreciate that.
