1986 5th ave idles ok but pops backfires through carberator

1986 CHRYSLER FIFTH AVENUE
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MPZBEST
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I have a 1986 Chrysler 5th avenue with 74000 miles 318 engine I filled up and went 6 miles it started to pop backfire. I changed the gas plugs wires battery. It back fires through the carberator but only when you step on the accelerator it idles ok and starts right off
Jun 16, 2007 at 12:14 AM
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DRAGONDON
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[quote:10b267136b="mpzbest"]I have a 1986 Chrysler 5th avenue with 74000 miles 318 engine I filled up and went 6 miles it started to pop backfire. I changed the gas plugs wires battery. It back fires through the carberator but only when you step on the accelerator it idles ok and starts right off[/quote:10b267136b]

Timing issue. The plugs are firing when the intake is open, thus creting a backfire throughout the intake.

Check all your vacuum lines, in particular the one that goes to the distributor. Regardless of anything else, replacing them is a necessity on older cars.

Next, you probably have that Lean Burn computer, wouldn't be surprised if that's got down the drain.

Get on over to www.allpar.com and get into the FMJ-body message forums. There are guys there who can explain issues with that better than I.
Oct 15, 2007 at 5:15 AM
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