Got an 88 burb 5.7l and theres enough black smoke commin out the tail pipe to mislead you to think its a diesel. engine runs rough and falls on its face, even at idle. like i said inside of tail pipe is black, while at idle there is a lot of fuel just dripping off the throttle blades, is this normal? I was thinkin about swapping the TBI and callin her good....? Local shop said valves need to be ground.......but i never heard of one of these havin valve issues before.

 

O2 sensor failing,coolant temp sensor resistance out of spec,sticking injector is there a cone shaped spray pattern coming out of the injector a little puddling on top of the throttle plate is normal,is there black smoke when the engine cold,wouldn't hurt to check the TPS resistance while your in there

Sean

97 4x4 burb

 

defiantly running rich... as mentioned above check fuel delivery

 

yeah smokes when cold--i know its runnin too rich. i know shes got good spark--but i was told someone else before me was in there tryin to set idle and if i remember right didnt gm get rid of the oblonged holes to eliminate people from adjusting that? (normally they cause more problems than they solve) The guy who ownes it dosent drive it much, but he is kinda a stickler on money. Its not just a puddle on the blades, its a pool where is the pressure reg on these? tank?

 

its in back of the injectors in the center of the TBI unit


Sean

97 4x4 burb