I have an 87 Cutlass Supreme with a 307 in it. The engine had been running really rich for a while and chugging the black smoke under hard acceleration. A knowledgeable carb guy in town offered to rebuild the carb for me and try to fix the problem.
When he finished, I reinstalled it, cranked the engine and she fired up and ran good. It idled good for about five minutes and then all of a sudden it start idling real rough and eventually died. I started it up again and it just died again. Started it up again and gave it some gas, held the throttle for a bit and then let off and it stayed running but idled terribly rough. It sounded like there was a lumpy cam in the motor. i decided to take it for a drive and on the open road it ran good. When I came to a stop sign, it idled really rough again and acted like it was going to die again.
I unhooked the battery to reset the computer and nothing changed. In order to make the thing run, I have to start it up and hold the throttle down for a minute or so. It runs choppy at first and then gradually starts running smoother and smoother and the missing disappears. If I don't keep my foot into the gas right from start up, it will just spit and sputter and die. Even when I get the thing to idle it stills sounds like a Pro Stocker and acts like it wants to quit.
Can somebody give me some suggestions on what could possibly be the problem??? Could I have hooked a vacuum line up incorrectly??? Intake manifold blown??? EGR valve???
PLEASE HELP! Thank you.
When he finished, I reinstalled it, cranked the engine and she fired up and ran good. It idled good for about five minutes and then all of a sudden it start idling real rough and eventually died. I started it up again and it just died again. Started it up again and gave it some gas, held the throttle for a bit and then let off and it stayed running but idled terribly rough. It sounded like there was a lumpy cam in the motor. i decided to take it for a drive and on the open road it ran good. When I came to a stop sign, it idled really rough again and acted like it was going to die again.
I unhooked the battery to reset the computer and nothing changed. In order to make the thing run, I have to start it up and hold the throttle down for a minute or so. It runs choppy at first and then gradually starts running smoother and smoother and the missing disappears. If I don't keep my foot into the gas right from start up, it will just spit and sputter and die. Even when I get the thing to idle it stills sounds like a Pro Stocker and acts like it wants to quit.
Can somebody give me some suggestions on what could possibly be the problem??? Could I have hooked a vacuum line up incorrectly??? Intake manifold blown??? EGR valve???
PLEASE HELP! Thank you.
