New to forum and looking for help/suggestions. Have 89 Iroc with 5.7 TPI auto. Problem I have is a miss or sputter when I get on it , whether it's taking off from stop sign or hammering on it. When it was real hot here drove it around and car almost stalled out like it was outta fuel but I'd let off and it'd come back to life. When I got it home there was thumping sound in tank, I opened gas cap and it hissed for like 30 seconds followed by loud thump and pump whine/ turning off. Fast forward to today I replaced intake temp sender cuz 1 fan wasn't turning on. Now miss hesitation is way worse, can't even brake torque or hard accel. It's like rev limiter kicking in it just hits wall and starts shuddering. Thought maybe pump was on way out. Any ideas would be appreciated. Thanks

 

Have you checked the fuel pressure under load? Sounds like a combination of high ambient temps and an overheating, failing fuel pump may be having problems with fuel vaporization on the suction side of the pump.