Chevy 88 Astro van V6

BMOLLAT1

MEMBER
1988 CHEVROLET ASTRO
6 CYL
2WD
AUTOMATIC
164,500 MILES

Hello, I have a 1988 chevy astro van v6 and it has been running rough on idle and when I step on the gas it rev's but then dies out, I, changed cap rotor n plugs on it and air cleaner, it runs smoother, still rough though and still when I step on the gas the motor revs then cuts out, tried advancing and retarding timing, helped slightly but still it will not run at a constant rpm, at one speed. I have to slightly feather the gas pedal. Also no fuel injectors, I see a carb on it, looked for the air/fuel mixture and wanted to reset but did not see any, are they inside the barrels of the carb? Any suggestions?
Merry christmas!
Bryan

1 Reply

HMAC300

MECHANIC
48,601 POSTS

Those carbs have a littlevalve that controls anotherone thattrys to adjust the mix. Probably what is wrongis that the alcohol in todays fuel has wrecked the accelerator pump plus it being a rochester it may have a vacuum leak creating your problem. Make sure all your fuel filters and fuel pressure is ok though. This may have a tbi unit that looks similar to a carb. The connections on top of the injectors lose contact and the gasket below the tbi unit blows so it causes a vacuum leak as well. Try those by spraying choke cleaner on the bottom of the carb/tbi. If the rpm changes then it's got a blown gasket.