1980 Pont Bonneville Brougham - Runs & Dies

[alphaauto]

Yes i said 1980.....Scratching my head on this one..To begin.

Grandpa gave car to niece, 88k only, clean car. Had towed in, because he tried putting spark plugs in it; couldn't reach under a/c compressor. Ok we finished tune up. Cap, rotor, wires, plugs & replaced corroded module. Car started & ran, but when got warmed up shutoff at idle.Would restart no problem. Asked customer if this was the issue for his reasoning for tune up. He states yes.

Seems to me it was a fuel starve issue, at idle spray with carb cleaner a tad & will run. Figure bad fuel filter. Pulled filter & couldn't even blow through it. Changed filter, car won't even stay running have to drive with two feet to keep idle up. Replaced fuel pump figure weak. Car starts & runs at high idle fine, nice throttle snap, keeps up. Even idles better. Cool, done? Nope!!! Let warm up died out. Pulled back in garage for night. Same thing all over, starts, runs, tries to idle, dies out. Starts right back up???????

Comments,suggestions??????/

[steven kiser]

yeah baby, a rochester quadra bog. sounds like a air bleed issue to me or an egr stuck open. the gasket under the carb may be junk. be real careful on these. with it running spray around the base of the carb with carb cleaner. if it starts running fine there is a gasket leak. do not try to "snug" it up. one of the rear ears will probably snap. another issue is the "pcm" controls. see if there are two leads at the distributor. i believe the the seven wire connector is the one that controls. un plug it and see what happens. there is a shut down valve in the carb. this was in the years of emission development and was a black time in out industry. if unplugging the connector resolves the issue reset the timing and ship it. i can almost guarantee the more you try to fix it "correctly" the bigger hole you'll be digging. as we all know i'm not an advocate of mickey mousing but this may be an exception. another tip here, look at the drivers side motor mount. if there isn't a safety cable there install one. this vintage had a habit of tearing the drivers side mount and lifting the engine high enough to destroy the shroud and more importantly pin the accelerator cable so the engine goes wide open throttle.

[fortknoxx]

wow. dies when warm. here are a few ideas to check along with steves.

is that tube from the airpump check valve getting cherry near the bottom when it dies?

hei coil in cap? check the flat module (control) to see if there is still grease on the metal side where it mounts.

not hei, check the coil for oil or oil residue on or around. coil is insulated with oil. if oil is gone it could be overheating.

look along the firewall. make sure the harness is not hanging down on exhaust.

[liljoe]

Steve, I think a 80 model has the 301 with the 2bbl version of the qjet, I think I would be looking to see if the air screws have been uncovered yet and if not would be drilling and removing the caps to alow for an air mixture adjustment, unless of course the carb spray is picking up a leak somewhere besides the carb, not sure where he is spraying the cleaner at.