Intermittent no start/run, lots of tests done!!!

1993 BUICK REGAL
133 MILES
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STANGIN
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I have a 1993 buick regal with 3.1 liter. car started stalling off and on over two week time period. Eventualy the car would not start at all. So far i have tested the crank sensor, map sensor, camshaft sensor, the ecm, and ignition module. also did secondary resistance test on the coils. it has spark, it has 42 lbs pressure at the rail, the regulator is not bad. the weirdest thing is the only thing that would get the car to start is to choke off the throttle body manualy. after started the car runs great, and then eventualy after so many restarts it will not start once again. im lost!!!!!!!!!!!!!
May 29, 2012 at 1:20 AM
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ASEMASTER6371
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check the coolant sensor. it may be out of spec.

Roy
May 29, 2012 at 1:22 AM
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STANGIN
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good point, will do right now
May 29, 2012 at 1:26 AM
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STANGIN
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coolant temperature sensor checked out good
May 29, 2012 at 1:39 AM
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ASEMASTER6371
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how did you check it??

if you disconnect it, it should turn on the cooling fan thinking it is overheating.

if you short the 2 wires together, it should go full rich.

Roy
May 30, 2012 at 10:51 PM
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STANGIN
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well 1st time i unplugged it, then i checked the resistance while heating it up, didnt seem quite right so replaced it, still have same problem. id like to add couple things, egr valve checked out good, it isnt bad gas, but the weirdest thing is today i swaped out the computer with another one out of a running vehicle that had matching numbers. didnt fix the problem but when i put that one back in the running car it caused it to not start well, it would do same thing this car does for a few times. disconnected battery for 10 mins and it went back to normal. also, yesterday i had car running all day, left it idel hour at a time for few times, at least 20 restarts, and drove for about 20 miles. then randomly i went to start it and same problem, rrrrrr!
May 31, 2012 at 12:45 AM
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ASEMASTER6371
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did you change the prom form your computer to the donor computer??

Roy
May 31, 2012 at 1:02 AM
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STANGIN
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wow, i feel like an idiot right now cuz i didnt even think of doing that, i will try that tomorrow, on another hand if no different, do you think something is sending a short back to the computer?
May 31, 2012 at 2:01 AM
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ASEMASTER6371
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not likely. try the prom first.

Roy
Jun 1, 2012 at 1:49 PM
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