Pontiac Problems? Ask a Mechanic for Answers ASAP
Hello and welcome!
With no codes being set it is very likely that your crankshaft position sensor is failing. Especially if this is only occurring intermittently, i would replace the sensor. I have seen this problem before and it normally happens when the engine is hot. The crankshaft position sensor is located behind the harmonic balancer and a puller will be needed to remove the balancer.
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