1986 Pontiac Parisienne starting trouble.MAJOR!!

[jamik]

Could anybody give advise on how to possibly fix a starting problem, will explain more when someone replies. It's very sick!!

Last year I was driving it, and at highway speed, the HEI clip disengaged from the distributor. The car jolted really bad, and died. Smoke and slight flames from carberator, but reconnected the clip and car started no problem. Next day, really hard start at cold. Car would only start if I manually held open choke, and would run perfectly after. Had to repeat process any time engine completely cooled.
This year, problem still not fixed. Decided to change 20 yrold OEM catalytic convertor, and installed a new Magnaflow Performance Cat. Car ran fine for about 2 hrs, then it kept wanting to stall. Thought there was a problem with the carb, so I put on a replacement carb I have. Worked beautifully for about 5 hrs, then the RPM went sky high, threatening to damage Transmission. Tried adjusting Idle, wouldn't work. Put on original carb and RPM still sky high. Tried adjusting, turned down Idle, car stalled. Reset Idle to where it was, car ran, shifted it into drive, went to pull out and car died immediately. Same recurring problem anytime it's started.
Also noticed that gas is somehow getting into vapor canister.

[DanD]

With your last comment

Also noticed that gas is somehow getting into vapor canister.

The carb maybe flooding, forcing fuel out of the float bowl vent into the carbon canister.
Try clamping off the rubber fuel feed line at the fuel pump with a pair of vice grips. Start the engine and allow the carb to run dry. If the carb is flooding as the fuel level goes down because of the clamped line; the engine will start to run normally for a few seconds up to a minute until the fuel runs out. Remove the vice grips and restart the engine; this may flush any dirt that maybe stuck on the needle and seat.
Again if the carb is flooding and this doesn’t clean itself up; you maybe into pulling the top off the carb and cleaning or replacing the float, needle and seat.
Give it a try and let us know the results.
Dan.

[oldtimer5520]

Hi Jamik,
Have you checked the vapor canister valve? They used to go bad and suck fuel from the carb and put it into the vapor canister