mwhitney86

Ive done an engine swap and when it starts it idles high and runs for 8-12 secs then dies as if it is running out of gas. Ive started from the tanks and blown out all gas lines, replaced fuel filter under skid plate, tried a different high pressure fuel pump, have checked all vaccum lines. I cant hear the fuel pump on the frame kick on and cant find the schrader valve on the fuel rail to check pressure. Need help have too many hours into this project. Have a haney book but not sure how to test with omh meter.

Big Jess

Maybe something with the computer?, I had issues with my 86 plugged in a morse code like reader. Little red light would flash on and off. Idk where you would get one these days, ebay? Good luck!

klricks

From other discussions here I seem to remember that the scrader valve may not be present on some engines.
The computer shuts the pumps off after 2 seconds if the engine dose not start. For testing you can force the pumps on by shorting pin 6 of the test connector to ground.
http://img195.imageshack.us/img195/4084/obdicon.jpg

For details follow the link in my signature below.

Old tired rebel

If you use this link it will help. Pull the codes and see what comes up it is easy to do. Sounds like the IAC is bad but this will help confirm what is wrong. I used this to find mt TPS and IAC was bad.

http://oldfuelinjection.com/?p=13

walter34payton2002

I used to have an 85. Same truck. I sold it. MAJOR pain in the *** with the fuel system and never could get it right. There is no schrader valve so don't waste your time. What I did was pull one from the yard and swap it. I had fuel system nightmares on the 85. Anyway, I was stumped for a while thinkin I had timing/ fuel issues and it was the PCM (I did have other fuel issues). Make sure your PCM is good. Do you have good compression? Your fuel filter good? There are 2 pumps. When you ground a pin on the eec interface you can run pumps constant to see if they work. Its in Hanes. Make sure your fuel system wiring is good. There were major problems with the dual tanks and wiring with them too. Make sure wiring to fuel pump relay good. I had to rewire fuel system too.....