lean problem with 1994 s10 4.3-help
 

I have a problem with my 1994 s10 blazer with a 4.3 vortec that has thecpi system. It dose not idle but if I spray starter fuel in the intake hole it will run fine at idle. I have already replace the injector system and check the fuel pressure which runs 58-60 psi. I alsocheck the vacum which is at 17lbs, and the EGR vaule is good and clean, replace mass air senor to. all that is left is the computer but it dose not give a bad code saying its bad, it dose give me a masa air senor code still even after replaceing it. at higher speeds there is no problem.
Anyone know what could be the problem?

RE: lean problem with 1994 s10 4.3-help
 

94 CPI motor does not have a mass air flow sensor... MAP, manifold absolute pressure, sensor yes.

What is your fuel pressure at idle?

RE: lean problem with 1994 s10 4.3-help
 

Sorry you are right its not the mass air flow sensor...but MAP, manifold absolute pressure sensor and the fule psi is 58-60 psi

do you have a idea of what i should look at?

RE: lean problem with 1994 s10 4.3-help
 

Good fuel pressure. Almost sounds like you have a pretty serious vacuum leak causing a lean condition at idle. More fuel corrects the problem. I would start by checking all vacuum lines over for cracks or breaks.

RE: lean problem with 1994 s10 4.3-help
 

NO I have check and the vacum is at 17lbs which is real good , do you have any other ideas?

RE: lean problem with 1994 s10 4.3-help
 

test TPS (throttle position sensor) and O2 sensor Using a scanner.