1993 GMC Sierra 1500 runs but back fires
After 30-50 mins of driving, when you try pick up speed it back fires. Don't know what
the problem might be. Maybe the distributor?
Yes, maybe. Backfiring is unburnt fuel exploding in muffler or cat, and if your distributor is vacuum advance make sure the vacuum hose is attached and timing is good, Unburnt fuel is somehow making it's way through and is collecting in the exhaust then detonating when you throttle up. Suspect timing
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