95 GMC 1500 5.0

[Dewitnow]

I need some advice, like the title says, I have a 95 5.0. It doesn't want to idle, it also doesn't want to accelerate. It runs better when it's cold but when it goes into open loop it falls on it's face. It is mnot giving a code unless I disconect one of the sensors. (interesting thing - it doesn't give a SEL when I disconnect the 02 sensor)

 

I have changed;

cap/rotor/wires

pickup coil

distributor

fuel pump/filter

fuel press regulator

idle air control valve

 

Items I've checked that seem to be in good condition;

throttle body injectors Have a nice spray

02 sensor checks out according to "Haynes"

engine temp sensor checks good

EGR kills motor when checked

Looked for leaks around the intake/throttle body with starting fluid - checks good

 

Parts are getting pricey!

The distributor was $200 plus!

 

I think the SEL should come on when I disconnect the 02 sensor so now I'm wondering if it's the computer.

I only have one 02 sensor so I don't think it could be the CAT.

 

Ideas?

[grampadirt]

Check the MAP sensor & TPS.

 

Also,the engine starts in Open Loop and goes to Closed loop when the O2 sensor gets warm enough.Are you sure you checked the correct temp sensor?The one by the thermostat? How do the grounds look at the thermostat housing bolts?