jlang

I finished a frame off restoration of an ’86 F150 about 2 years ago. I’ve always had this issue. The issue is that if the outside temperature is above 65°F and the truck is sitting at a stop light, after a minute of idling it will start to run a bit rough and progressively run rougher until it is barely running. After about 10 seconds of trying to stay running, it shuts off. It spins over but it will not start. I need to let it sit for about 5 minutes before it will start again. Here’s the thing, once I start driving again, it’s fine. This once happened at a major intersection in the middle of a city and I needed to push it into a construction site to let traffic through. I let it cool off and I took back roads to avoid any long stops. The warmer it is outside, the quicker it shuts off, so it’s heat related. I believe I have it narrowed down to a failing in-tank fuel pump. I think, when that pump fails, the high pressure pump is forced to siphon gas from the reservoir/tank selector (I hate that thing) and for some reason the gas may be vaporizing. Below 65°, the truck will idle all day long, regardless of whether the in-tank pump is working or not. Has anybody run into this before? The main problem is the pump failing. It lasts about 1000 miles then I just replace it and things work fine again. I’m only using the one tank so I don’t think I need the reservoir/tank selector. I would like to install a high pressure pump in the tank and remove the high pressure rail pump and the reservoir/tank select, similar to the ‘90’s F150’s. Has anybody done this before? I think I can just route the high pressure rail pump wires to the tank pump wires. Any advice would be greatly appreciated.

klricks

Do you have the 302 EFI? Only the EFI has a high pressure pump. Not matching the engine shown in your profile 351 2V?

For the stalling issue. Look into replacing the fuel pump relay. I had a stalling problem which gets worse in hotter weather. The engine would buck and then stall while driving at anytime. I found that if I attempted to start the engine, it would never restart UNTIL I switched the ignition ALL THE WAY to OFF and then back on again. When I switched off and on, the engine would immediately restart and run fine for 20 minutes or so.... Before I discovered that I had thought that I must wait for a cool down period..... I got really good at restarting the engine in moving traffic without the embarrassing coast to the side of the road....
I just replaced my fuel pump relay and so far OK but have not driven enough in warm weather to verify.

Note I have removed the Reservoir thing.... Extensive write up on my web site. Have to fix my site though as my picture host web site deleted most all my images.

jlang

Thanks for the response Klricks. I will try a few things and let the forum know what, if anything, solved the issue.