101btp

iTrader: (1)

alright today was not very good, I have a 1986 trans am running a 305 with the stock carb, the weather has finally warmed up and I got the last tire on today, I decided that it might be a good day to take a run, the carb back fired leading to a small fire nothing major but enough to run flames out the top of the hood for a good few seconds, my question is would my vacuum leak be the cause, I replaced the seal around the bottom of the q jet spread bore carb, but I still spray starting fluid around the carb and it still picks up idol? o it also for a while had produced a popping sound when I put the pedal down but no where near shooting flames out of the carb, and suggestions? carb rebuild?

101btp

iTrader: (1)

O i forgot to add that after this had happened I did manage to start it up with the help of a little starting fluid, but when it did start up for about 30 seconds the engine put out a much deeper tone but not as loud and almost un able to go high up on the rpms

five7kid

iTrader: (14)

Carb backfire is almost always a lean condition. Could be from an inoperative accelerator pump (most likely needing a rebuild to address), or from a vacuum leak (most likely a "standard" rebuild will not address).

Is the SES light coming on? What's the history of this car, has it been sitting for a long time? You comment about getting the last tire on leads me to believe that is the case. How fresh is the fuel? How fresh is the ignition tune-up?

101btp

iTrader: (1)

well I just went out side just to make sure I did start it up and my SES light was not on and yes it dose work lol, I just took all winter to get the tires changed, but it did have in it winter gas with added octane booster, no real ignition tune up other than new wires, I talked to a mechanic and he said it could be coming from my distributor, im taking off school Monday to hopefully get some needed work done on it, here in not that long i might be running into about 1k to spend on it so im not sure if I just might want to invest in a new carb for it? just to save the re build it dose need, the gaskets that are on the carb are a little beat

naf

iTrader: (7)

A rebuild will cost you around $30-40 in parts. You may want to try it yourself before spending $ on a new, reman carb. You may also want to cap off each vacuum port and try the carb cleaner around the base again.

I'm also seeing more of these carbs with worn throttle shafts which can cause a vacuum leak. Try the spray around the primary shaft at the throttle cable then take the cables off and check for play. The shafts can be re-bushed which will add a little to the rebuild cost.