1994 Chevy Blazer 94 Chevy Blazer revs and shakes

SONOFBRAHMS

MEMBER
1994 CHEVROLET BLAZER

Engine Mechanical problem
1994 Chevy Blazer Four Wheel Drive 109000 miles

I have a 1994 Chevy Blazer that was running fine yesterday. After driving it around for about an hour the check engine light came on about half-way home and the car started revving and cutting out when at a stop light or going slow. I was almost able to let it drive itself through the parking lot when it was revving! Today when I started it again (after adding HEET, as it was really hot and humid yesterday), it shook when idling and started revving again when I drove it around the parking lot.

I have checked the air filter, coolant levels, and put in HEET to make sure there wasn't water in the fuel line. Is it possible that this is a fuel system problem (filter etc.)?

1 Reply

HMAC300

MECHANIC
48,601 POSTS

I suspect this is the TBI unit on this vehicle. Spray some cholke cleaner while running around the bottom of the TBI unit and if the idle changes, you probably blew the gasket under it which is a common problem. If it's not and has the L35 engine in it take the same choke cleaner and clean the throttleplate and IAC hole while the engine is shut off. Clean both sides of the plate as well as the TPS switch. It may be hard to start after doing this, then see if it has changed. You could also have a vacuum leak through the throttle shaft as well. But try that stuff first.