i recently bought a 1989 f-150 and had both fuel pumps and filters replaced, now when i go to start her, she starts fine, but quits running after a minute or so of idling, plus as soon as i put her in gear, she dies. what could be wrong with my truck?
any info will be very helpful, allen gibson.

 

Idle Air Controller.
Mounted on the throttle body.
Remove and clean with spray can cleaner.
Re-install and test.
Would be good idea to clean the bore of the throttle body at the same time.
This is where the air for idle is controlled by the computer.
There can be other reasons for stall after a short time cold running but try this first.

 

If that doesn't work, try a regular tuneup. Plugs, wires, cap and rotor. Is the CEL on? If so check the codes.

 

I am assuming you have dual tanks and replaced the pump and filter in each tank. I believe the 1989 still has the third fuel pump in the left(drivers side) frame rail.(89 was last year though) There is also another filter in the line between the tanks and the engine near the left frame rail. On my 1988 F-150 it is right even with the back of the engine , drivers side, just above the frame. I would replace that filter if you haven't already. If you keep your engine at a fast idle, will it run longer than a minute? When it quits will it start back up right away? What made you decide to replace the pumps in the first place?

 

the lady who owned the truck before me had the fuel pump in the tank replaced and everyone was telling me it was best to change the other one also, so i did. Now i have changed the plugs, wires, air filter, fuel pumps, fuel filters, battery and now the fuel pressure regulator.
now she runs for a few seconds and when the check engine light comes on, she immediately dies. My uncle is bringing his code reader over this weekend. Im hoping its just a sensor and hopefully i'll have my girl running finally.
thanks for the help and advice everyone...

 

On my 89 f150 and it was a speed density one too. The engine would surge and die too, sometimes it did it will I was making a left turn..... not good when you need the power steering to turn

I clean, replace IAC even replace the computer with a spare I had and still had that problem. So i drilled one 1/8 hole in the top butterfly valve of the twin 50mm throttle bodies. And so far so good, that was like 10 years ago and some 250K miles later. That truck would still be around if I didn't turn it into a trailer for my Dragbike. Oh yeah that motor is sitting next to my house waiting to go in my 65 Falcon come summer