Dat_1995_Z71

1995 Chevy K1500 5.7 tbi. Idles fine and when revved in park or neutral it revvs fine but when put in gear and trying to accelerate it starts bogging and will stall if I dont let off the gas. If I let off it goes back to idle fine and if I barely accelerate it wont bog, just after trying to accelerate past maybe 5mph. Changed the fuel filter, spark plugs, plug wires, all plugs are getting spark, the injecters above throttle body spray fine at idle (dont really know how to check spray when trying to accelerate). Vacuum hoses around the motor seem fine no noticeable leaks. Transmission went bad it lost a gear so it was parked for about a few months had no gas in it and decided to drive it one day down the road so i put gas in it and started to go down the road and thats when i noticed the problem. Changed all the parts i said was changed and still same result. Only other thing is one night i was trying to move it to the back yard and it started bogging and i didnt let off the gas and it stalled and the throttle body caught on fire but that only happened once out of like 10 stalls. Cranks right up after stalling and still idles fine. Only other noticable thing is that when at idle I can hear what to me sounds like a little skip in the sound of the exhaust at the tips. It is true dual straight piped no cats or mufflers and does have a small exhaust leak where the passenger pipe bolts to the manifold but that never made it have that skip like sound in the exhaust when i got the exhaust done. Any suggestions?

Gumby22

Sounds like it probably isn’t getting adequate fuel supply and is leaning out as the engine is under load.

One of the most common failures/problems with these trucks are the fuel pressure regulators going bad; usually due to excessive contamination buildup inside the injector body.

Check the fuel pressure key on, engine off. It should be 10-15 PSI and hold for at least 2 minutes without dropping below 10.

If it drops below 10, first try blocking or pinching off the return line and retest - if it holds now, the regulator is the problem. Repair kits are available at almost any parts store.

If it doesn’t hold pressure with the return line blocked off, OR if it loses pressure at a slower rate, the fuel pump check valve is faulty and the pump needs replaced.

That said, if the pump is producing adequate pressure at key on, you’ll probably be OK waiting to replace the pump until the regulator has been repaired.