My car was down for a while while I performed a complete brake job. It's back running on four wheels now (brakes work fine!) but it seems to have developed a backfire. It's not real loud, but at idle up to about 2000 RPM I get an erratic backfire every few seconds or so. Once on the road or highway, I can't detect any backfiring and the car runs strong. Just starts backfiring again when it returns to idle speed.
Before I start tearing things apart, what are the most likely causes of such a backfire, hopefully in order of most likely to least likely, for me to check?
Causes for backfiring on a 356B
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Paul Giganti
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Re: Causes for backfiring on a 356B
Crappy ethanol fuel has clogged your idle jets.
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Jules Dielen
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Re: Causes for backfiring on a 356B
small exhaust leak?
Jules
Water pumps are for windshield washers only.
Water pumps are for windshield washers only.
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Jim Liberty
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Re: Causes for backfiring on a 356B
At idle is usually jets and at deceleration is usually exhaust but maybe not.
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David Jones
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Re: Causes for backfiring on a 356B
Open up the mixture screws a 1/4 to 1/2 turn and see if that helps. Ethanol fuel makes the mixture tend towards the lean side.
If I had known I would live this long I would have pushed the envelope a little harder.
Cymru am byth
David Jones #9715
Cymru am byth
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Tim Berardelli
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Re: Causes for backfiring on a 356B
Paul,
Easy way to determine which carb. or cylinder has an idle jet issue and which one is blocked, is to spray a one second burst of carb. cleaner, in each throat, with engine up to temp. When the idle speed increases after a squirt you have found the culprit.
Tim Berardelli
Easy way to determine which carb. or cylinder has an idle jet issue and which one is blocked, is to spray a one second burst of carb. cleaner, in each throat, with engine up to temp. When the idle speed increases after a squirt you have found the culprit.
Tim Berardelli