In the beginning it would start but wouldn't idle. Had a bad surge in the idle. Changed out the distributor, cap and rotor, fuel filter, fuel pressure regulator, wires, plugs, and spider. Fuel pump is about 4 months old. When I unplug the timing connector it runs and when I plug it back in it starts but immediately dies. Can anyone help me figure out what the problem is? I would really appreciate any input.

 

is it timed to zero with that thing unplugged?

i remember on my 90 you had to unplug it then put the distributor to zero then plug it back in

 

If the timing is correct, then there could be a problem with the ICM that is causing it to command too much timing.

 

How do you set the Timing on a 92 4.3 MFI VIN W, this has been the million dollar question for me, I know you have to set the base line at zero but how do you cut out the computer to do this? Mine gets crapy gas mileage and when you rev it, it will almost die and when you start it after running a while it will idle up and almost die or die all together, then you have to hold the pedal to the floor and try to restart.

 

You have to first disconnect the EST bypass connector wire (tan w/ black tracer near the distributor in '92).

 

Is that coming off of the destributor? If so I have pulled both one at a time and the engine would not start. If you can, send me a wire diagram or give a better description. I do appreciate the help, I am just lost right now, never dealt with computer stuff. I am more into noncomputer engines.