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car backfires under deceleration from 3000-2400rpm

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Old 05-07-2010, 10:30 PM
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Car: 1987 iroc z
Engine: 350tpi
Transmission: 700r4
Axle/Gears: 342
car backfires under deceleration from 3000-2400rpm

i just replaced the distributor with an msd and the car started to backfire under deceleration with flames shortly after. what would cause this. its probaly a good 10 small-large backfires during each decel. more like pops in the exhaust not really loud like gunshots or anything iots just really annoying people complementing the flames lol. please guys help me
Old 05-07-2010, 10:33 PM
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Car: 1987 iroc z
Engine: 350tpi
Transmission: 700r4
Axle/Gears: 342
Re: car backfires under deceleration from 3000-2400rpm

also if this may have anything to do with it during the install of the dizzy i have hooker headers with the air tube capped off on the end and 2-3 of the tubes snapped near the header so its leaking there.
Old 05-08-2010, 11:42 AM
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Car: 1995 Corvette
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Re: car backfires under deceleration from 3000-2400rpm

What did you set your ignition timing to? This sounds like bad timing..
Old 05-08-2010, 07:45 PM
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Car: 1987 iroc z
Engine: 350tpi
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Axle/Gears: 342
Re: car backfires under deceleration from 3000-2400rpm

About 10 degrees
Old 05-09-2010, 01:41 AM
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Car: 83 POS monte carlo 2015 chevy P/U
Engine: 92 5.7 tpi 5.3
Transmission: 700r4 6L60E
Axle/Gears: 2.42 too high
Re: car backfires under deceleration from 3000-2400rpm

with a leak like you have, under decel it will pull fresh air into the headers and will cause a backfire in the exhaust.
you'll need to get the leaks fixed.
Old 05-09-2010, 10:10 AM
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Axle/Gears: 3.25:1
Re: car backfires under deceleration from 3000-2400rpm

+1

Exhaust leaks up near the engine will cause what you describe.
Old 05-10-2010, 12:38 AM
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Re: car backfires under deceleration from 3000-2400rpm

im gonig to weld them up next chance i have...hope you guys are right.
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