Hello. I have a 98 chevy 1500 5.7. The truck doesnt run right at all. Msifres bad under acceleration. Idles ok but misses when reving and accelerating. I did a full tune up including plugs, wires, cap rotor and a new distributor. With key on I have about 60psi fuel pressure but idleing I only had 50psi. I put a complete new fuel pump unit in and changed fuel filter. Same problem. No different fuel pressure. I changed and replaced the spider injector with the new updated system. Changed all intake gaskets. That didnt make a difference either. Replaced tps sensor and map sensor. Removed egr valve and it isnt sticking or anything. I cleaned it and used new gasket and put back on. Still same. I know these trucks need 60psi when idling. Cant figure out why I only have 50. I replaced everything in the system. I removed the fuel line where id goes into the spider system and plugged it and have 80psi when I turn the key. Then I disconnected the return line by the distributor and plugged it and had 90psi there when idling but engine ran the same. I dont know where to look next. Please help
have the same problem?
Tuesday, February 3rd, 2015 AT 10:53 AM