Running rich and backfires, bad timing?
#1
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Location: Indiana
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Car: 1988 Trans Am GTA
Engine: 305 TPI
Transmission: 5-Speed
Axle/Gears: 3:45
Running rich and backfires, bad timing?
Not too long ago I put in a new ecu, and all was going well for a few weeks. Then I started to notice I can smell gas when I'm sitting at an idle, and the amount of exhaust smoke I'm producing is large. I already had a good amount but it was mostly at startup or if I was doing a pull, now I can see it when I'm idling, and a person driving behind me can see it. If I let off the throttle and leave it in gear every now and then I have a very loud backfire, almost like a gunshot. Could I be running more rich and such because my timing is off? I really don't know much at all about timing, so I have no idea what I'm doing here, any suggestions or information would be greatly appreciated.
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Car: 1988 Trans Am GTA
Engine: 305 TPI
Transmission: 5-Speed
Axle/Gears: 3:45
Re: Running rich and backfires, bad timing?
#4
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Re: Running rich and backfires, bad timing?
At prime the fuel pressure will rise to about 43.5 psi. If it drops quick after the prime you have a leak in the system. Your looking at a ripped fpr diaphragm or leaking injectors. To see if it’s the fpr you can pull it’s vacuum line to see if there is evidence of fuel. There are other things that can cause the overly rich condition. Cts , tps or bad maf to name a few.