1973 Questions for all other cars Backfiring

1973 ALL OTHER MAKES ALL OTHER MODELS
20,000 MILES • 6 CYL • 2WD • MANUAL
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ESENIOR7115
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Engine works well, plenty of power. However, whenever I decelerate I get backfiring through the exhaust. I aso get a slight "pop" when turning off ignition at idle; a "bang" if I accelerate and turn off ignition.
Air pump has been disconnected.
Engine is 6 cylinder with 3 double-throat Weber carburators (one throat per cylinder).
Aug 30, 2008 at 4:40 PM
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RASMATAZ
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Check your fuel pump pressure-could be excessive carbons/hot valves-Ignition timing incorrect,wrong sparkplug heat range, Since you disconnected the air pump that places the diverter valve inoperative to cause it to backfire during deceleration and also the air/fuel mix adjustment-
Aug 30, 2008 at 5:01 PM