1990, 302, 5 speed manual, 4x4.

My truck started to stall out while driving, and got progressively worse over a couple weeks. Truck will run until the engine warms up, 5 minutes or so, then loses power and dies. Won't start again until the engine is cold.

I replaced the ignition control module as I read they sometimes overheat. Reset the timing to +10° while reinstalling the distributor.

Recently replaced the rear gas tank unit (tank and pump) but I'm running off the front tank.

Pulled the OBD 1 codes:
Key On Engine Off: 24, 81, 82, 87, 84... Memory code 87
Engine on Test: 21, 41, 33

Any suggestions on where to check next? Thanks in advance.

 

https://www.troublecodes.net/ford/

Lots of issues. First thing to do is a fuel pressure test with a gauge, you need around 40 psi or so.. Have you replaced the fuel filter? Have you tried switching tanks?

 

Yes, new fuel filter. I don't have gas in the new rear tank, and can't drive to the station. I'll get a can of gas into the rear and try that. Thanks