Car shuts off randomly, won't start until engine is cold
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You are both correct, vacuum leaks could be caused by heat or cold (although heat is not as common as cold) but if you don't have switching on the negative side of the coil the issue is not vacuum related, its electrical and has to do with a sensor or wire that is effected by heatLeave a comment:
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Not always true...when things expand, vacuum leaks can develop at places like the throttle body or valve cover.Things expand when warm, usually vacuum leaks are present when cold, but not warm. That doesn't make sense to me. Also, the fact that it doesn't even try to start at all, like no cranking, means that it's probably not a vacuum problem. Sounds more like a grounding issue. The hot/cold thing doesn't make sense though.
The only thing I can think of is heat soak. A hot wire will have a greater resistance than a cold wire. So it may be that something is getting funky when the hot engine heat soaks the engine bay.Leave a comment:
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Things expand when warm, usually vacuum leaks are present when cold, but not warm. That doesn't make sense to me. Also, the fact that it doesn't even try to start at all, like no cranking, means that it's probably not a vacuum problem. Sounds more like a grounding issue. The hot/cold thing doesn't make sense though.
The only thing I can think of is heat soak. A hot wire will have a greater resistance than a cold wire. So it may be that something is getting funky when the hot engine heat soaks the engine bay.Leave a comment:
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I changed the ignition coil with a new one, also I've tried to use a different dme and still won't start when warmLeave a comment:
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Borrow a working DME from someone. I suspect that the ignition coil is the culprit, but you said you tested it already.Leave a comment:
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Ok. Both sensors are good, Ignit ion coil does light up. I just put in a new coil, Cap and rotor, and crank sensorLeave a comment:
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If the sensors both turn out good, get a 12v test light, (if you don't have one autozone/advance/napa/etc. sell them for like $5) hook it to a ground and then hold it on the negative terminal on the coil. Have a buddy crank the engine, you should see it flicker. If it does, then you know the issue is with a sensor other than the CPS, if it doesn't then the ecu is not grounding the coil like its supposed to.
Edit: I would actually do this test firstLeave a comment:
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Check BOTH the speed reference and the crank position sensor, they are located on the bell housing by the slave cylinder, unplug them and test the resistance, they should be at 960 ohms +/- %10 (unfortunately I cant remember the wire colors to test). Using the same pins, also test for AC VOLTAGE....AC, not DC, have a buddy crank the motor over, you should see greater than 250mv AC. do both tests when the motor is cold, then start it and warm it up until it dies, then do the tests again. I'm willing to bet your sensors work fine when the motor is cold and then start to lose their response when warmLeave a comment:

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