Hi there,

I'm new but really need some help. I just bought a 1994 S10 blazer with the 4.3 Vortech with 52,000 miles on it. It was having problems starting sometimes, so the guy sold it to me for a good deal. The problem was that some times it would fire up and run perfect, or it would not start at all. I found good spark, and compression, but the plugs were bone dry and didn't even smell like fuel, so I opened the throttle body and poured a little fuel in there, and it fired right off. the fuel pressure is right at about 57psi and holds. I started researching the injector, and heard that they have been known to have problems. I found the fuel pump relay bypass, hooked fused power to it, and saw the fuel pressure rise, so then I took a 6 volt battery, and sent power to the injector, and saw the fuel pressure drop and return to about 57 psi. It did that every time I energized the injector. After that I tried to start it, and it was a bit flooded, but it started. So I thought that the injector was maybe not getting power from the computer. I plugged in a noid light to the wire coming from the computer, cranked it over, and it was flashing nice and bright. It was getting the signal from the computer, so I turned my attention to the injector. I heard they had problems, so I thought the selenoid in the injector was going haywire. I bought a brand new injector spider with fuel lines, put it all in, and I'm right back to where I started. It acts just like it did before. My buddy told me to clean all the grounds I could find, and the battery terminals, because maybe it wasn't getting enough voltage when the starter was cranking. I tried that and had no luck. I'm thinking now that maybe the computer is the problem.

Has anyone heard of a problem like this before? Is it possible for the injector driver in the computer to not send enough voltage? I'm running out of ideas, and don't want to buy a computer, and still be in the same boat. ANY HELP WOULD BE AWESOME!!!!

 

Try this... Next time it's in a no start condition disconnect the MAP sensor electrical connector and try starting it. I only suggest it because my brother had a '94 Pontiac that would run great until it died and then wouldn't start for anywhere between 15 minutes and several hours. All the injectors would lose power, drove us nuts, we even tried a different computer. Might be something similar? That solved it