Hey everyone, first time posting. I recently got a 1990 c1500 silverado truck, with the regular cab and 8 foot bed. It's got the 5.7 L 350 engine.

My problem is that it seems to accelerate normally at about 1/2 pedal, but when I floor it, it hesitates. The engine sounds like it's trying to take off, but the speed goes up really slowly. The truck as also died on me twice when I was at a stop and gave it a lot of gas to speed up to traffic.

I, not being a mechanic, think that the problem might be the EFI. I got some of the seafoam engine cleaner and put it into 1/2 tank of gas. That was a few days ago, and of now no clear improvement.


Any ideas on what else might be causing it, or how to check if it's the EFI? I will most likely be stopping by the family mechanic and seeing what he thinks.

 

If I were you I would start out with the simplest cheapest stuff 1st.
It sounds like the engine might be being starved of gas.
Try changing the fuel filter 1st, it may be clogged. And it should be changed
anyway cuz who knows how long it's been since the last owner changed it out.

I personally would start with the fuel filter and go from there.
good luck, post back if it doesn't fix the problem.

 

I will check the fuel filter, I think that that might be the culprit. Just today it worked fine, accelerating smoothly at full throttle but then it went back to the usual at the next light.

No idea when it was last tuned or had the fuel pump replaced. The guy I bought it from lives down the street so I can ask him. I don't think that it could have gone for 160,xxx miles without replacing the fuel pump but maybe it's possible.

Also, it seems to be a little hart to start. I will change the fuel filter, can't hurt, and then see where it goes from there. Will keep you posted.