1987 V20 Fuel / Ignition Problem

[C@ctusjack]

Hello all,

New member, long time reader. Long story short. I have a 87 V20 with 157K. When I start the truck it cuts off immediately, but if I start it and hold me foot on gas it will run (extremely rough) until it reaches operating temp. Put it on the road and will surge during stops. Get down the road a bit and it runs fine.

I've changed the plugs, wires, cap/ rotor, fuel pump relay, idler control valve, fuel filter, and ran a fuel system cleaner through it . I'm still having the same problem. I've reached my mechanical abilities in trying to trouble shoot this thing.

Buddy of mine told me it shouldn't be the fuel pump or it would also cut out when I was driving down the road. This is my daily driver. Any ideas or suggestions would be greatly appreciated. THANK YOU.

 

[89Suburban]

Sounds like she is dumping fuel in. I have those same issues but not as bad in colder weather. There are some troubleshooting tips and pics in the library.

Off the cuff I wanted to throw this out there. Anybody think that a buildup of rust and scale on the temp sensor tip in the intake could affect its operation and cause these issues?

 

[C@ctusjack]

I went in yesterday and changed the fuel pressure reg, throttle positioning sensor and the injectors. Seemed to run better, but not exactly right. Also cleaned the hell out of the entire throttle body. Got allot of buildup out of the vacuum inlet lines. After letting it sit while cutting grass, I went back to fire her off and now she wont even start.

What the hell is going on with this truck?