EFI Vapor-lock

Yes I know it cant happen.
I have a 89 f350 460 fuel injected. Starts perfect, absolute power house, runs like a champ until it gets warm at which point it losses power chugs then dies ( runs out of gas). When the weather is hot I can make it about 12 miles in the winter double that. I know that I have high pressure after the hp pump (a face full of fuel verified this) but at the rail I get a few drops of fuel and air then nothing. after a cool down period ( typically enough time to call a friend and tow it home) it fires up like nothing ever happened.

I have replaced both in tank pumps complete assemblies as well as the high pressure pump, filter, pressure regulator, wrapped the fuel lines, none of which has made a difference. I love this truck and have had it sitting for a couple of years just starting every month because it cant be trusted to drive. its now time to figure it out or make room in the shop. any help would be greatly appreciated.

pickup in dist, or bad fuel pump is what id be looking at

pickup in dist, or bad fuel pump is what id be looking at

Since you have done all that work on the fuel system, I would have to agree with Boss429. I had that same problem on my '90 Mustang years ago, it turned out to be the ignition control module.

This may not be the problem but. something as simple as a vented gas cap where the vent is stopped-up can cause this.

I chased this same situation on our 7.5L swapped dentside and never found a solution. It would run great when the temp was moderate, but once the weather turned hot, it would run fine for a few miles then begin to sputter and die. Poke the schrader valve and it was always just spitting vapor. Let it cool down for a while and it would run a little longer. I always just thought it was the result of our particular fuel system adaptation.

i had a dodge ram that use to do the same thing...
i did pretty much all the same things you have done..a friend of mine suggested getting the injectors cleaned i did that and it never missed a beat again...
the conclusion was the injector guy came up with was the ecu was detecting the engine was running lean when it was hot and shutting down the engine...anyway it fixed my truck...

Interesting conclusion on the injectors. Quite honestly makes sense. I was leaning torward the distributor guts or vented cap as suggested above as well.

Glad to see some good honest discussion and attempted problem solving here. One of the things that made this forum what it is. Knowledge at its finest.

Folks I want to thank you all for your ideas. Could someone expand on boss429,s idea that it is the pickup in the dist. I know it controls the spark and it makes sense that it would have a hand in timing the injector pulse but how would it affect the rail pressure?

riverlane wrote:Folks I want to thank you all for your ideas.  Could someone expand on boss429,s idea that it is the pickup in the dist.  I know it controls the spark and it makes sense that it would have a hand in timing the injector pulse but how would it affect the rail pressure?

It wouldn't effect the rail pressure but it is a common part to fail that would give similar issues that you are experiencing.

Module gets heat soaked and breaks down causing very similar symptoms almost the same temperament that you are describing. Would not effect fuel pressure however.

thank guys very much for the input. if I get her running I will be sure post the final solution..