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91 GMC intermittent ignition failure

I bought it new and now it has clocked 103,000 miles. i was up in the mountains off a dirt road, and the ignition stopped as if you had turned off the key. When I tried to restart it, I could hear the fuel pump as normal, the starter cranked it normally, but there was no ignition. I could smell the raw gas when I cranked it for 15 seconds. Over the next 24 hours, I tried 9 times. Finally I had it towed to the dealer, where it started perfectly and they could find nothing wrong. So now I don’t trust it. Should I install a new coil? Ignition module? I don’t know.

With the age and mileage on the vehicle, and how you describe the problem, the first thing I would suspect is the ignition module. Some parts store will test the module for free on the premise that if the module is bad you’ll buy the replacement from them. But if you have the module tested, make sure that it’s tested for at least a half hour. Sometimes it takes this long for the module to heat up before it shows a failure.

Tester