Hey there,
I have a 72 Duster that sits for long periods of time. It is my Brother in law's car and he lives out of state. 360 with a Holley 600 4 barrel.
Here in CA, the blend is supposed to be "up to 10%" but testing has been reported to be around 6%. Regardless, the color of the fuel in the filter and the bowls is a pale yellow green. The last time I put more than 3 gallons of gas in it was several months ago, maybe last fall? Not sure.I did put about a gallon in it recently since I didn't know how much was in it.
My point....
The car idles fine. I did have to replace the needle & seat in both the primary and secondary bowls. Under a load, it sometimes backfires through the carburetor, It is not consistent like it would be with a bad exhaust valve or worn exhaust lobe, just occasionally. The ignition system is old. The engine bay wiring is old. The alternator is not charging even though I have tried three alternators and a different voltage regulator.
Yeah....The car needs work as many do,,,,But my question is: Can old ethanol laced fuel cause a backfire like this OR should I be looking at the ignition system?
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