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TheAcolyte
11-28-2005, 04:15 PM
Perhaps someone can help me troubleshoot these 2 problems that I am experiencing with my 64' Olds, Jetstar 88 (330 engine, 2-barrel carb, HEI distributor):

1. Backfiring: when starting my engine, it backfires, or near-backfires (more commonly) during the first few few cylinder rotations; not while I am driving though. This seems to occur through the carb, though, my exhaust system has been previously damaged by earlier backfires. The HEI distributor was supposed to have fixed this, but it has not.

2. During cold, damp days (like today), the engine will start just fine, and then after running a bit, the choke gradually decreases until finally the engine dies, despite revving the engine, or even driving it. However, after letting the engine die, if I wait about a minute and then restart the engine, all runs normally. The only other solution is to drive the car for about 10 minutes with one foot on the gas and the other on the brake when stopping. Again, the HEI distributor was supposed to have fixed this, but it has not.

I should also add that when I last looked and cleaned the spark plugs, they looked like they were in good condition, while the wires came with the HEI distributor (off a 1980 GM), and also appear to be in good condition. Also, if one listens to the engine carefully, it seems to miss a beat every once in awhile (the engine was rebuilt in 1999, and the carb and choke were just rebuilt again recently).

Any ideas would be helpful and thanks in advance.

The Acolyte

vestpuzzle1
11-29-2005, 04:57 PM
Sounds like the timing chain is stretched???

Oldcar_Mechanic
12-04-2005, 04:15 PM
It sounds to me like you either have a lean running carb or a vacumm leak someplace.
Check all fittings on the intake manifold and also try pinching off the vacumm lines coming off of it to see if the miss stops.

Ron