1978 Ford Bronco back fire

1978 FORD BRONCO
500 MILES • V8 • 4WD • AUTOMATIC
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JACKDOG1978
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reset timing checked all vacum lines put new spark plug wires on engine backfires under load
Jan 7, 2010 at 10:51 AM
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JACOBANDNICKOLAS
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Have you checked engine compression? You may have a burnt valve. Also, are you sure you are getting a good hot spark, and where does it backfire from the exhaust or intake?
Jan 12, 2010 at 7:26 AM