My 1991 gmc sierra all of a sudden died at a stop sign and now won't start. Turns over but won't start
Most common is a fuel pump failure. but there are also others. Check for blown fuses first. Do you hear a fuel pump running when you just turn the key to on? It will only run a few seconds, if it does run then check for spark and injector pulse. If it don't then replace the fuel pump assembly and filters. Check the fuel pump connector, if the fuel pump assembly comes with a new one, use it. These are known failures.
For the GM TBI engines the ICM (Ignition control module) located in the distributor has a higher failure rate. It is cheaper and easier to replace verses the fuel pump. When the ICM dies or the pick-up coil fails you will not have spark or fuel (the computer cannot see RPM and does not fire the injectors) if the pump is weak or completely failed you will have spark but no fuel spraying. But before we get to deep when is the last time the fuel filter was changed, if it's not spraying fuel check that first. It is on the inside frame rail, drivers side. Ensure you use line wrenches as regular open wrenches will most likely round the tube fittings.
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