If you were driving your '94 Pontiac Van 3.8L and it died with no warning then 20 minutes later started right up what could have caused this?

Answer 1

CHECK YOUR FUEL FILTER

Another answerThis is/was a very common problem 3800 FWD engine usually caused by a wire break inside the crankshaft position sensor. Replacing the sensor may require a special puller to remove the harmonic balancer it you cannot remove it by hand. It is often possible to remove the balancer pulling my hand, with the bolt removed of course. Do not attempt to use a jaw type puller to remove the harmonic balancer as this will destroy it.

This symptom can also be caused by a faulty ignition control module or ignition switch. If it's the ignition switch, wiggling the key around while the engine is running may cause it to stall or cause strange behaviour of heat/air conditioning or exterior lights. A faulty ignition control module is more common than an ignition switch problem, but can't easily be tested without both a digital multimeter and an oscilloscope so it it usually more practical for the DIYer to just replace it. It can be well worthwhile to apply thermal paste aka heat transfer compound which is readily available from any computer store. Silicone tune up grease is not the same thing and has the opposite effect.