Davidd

I have a 87 F250 4.9L 4 speed. I recently acquired the truck has a new long block. You can drive it and it runs great for about 20 min. Then It dies like its running out of fuel.It will start back up but only idle.Let it sit not running for 15 min and off you go again. The fuel tank selector valve was leaking at the bowel so I replaced the seal and havent yet driven it. Could it have been getting air and hence the reason for it dying?

Bert

The fuel pressure should be checked when it's doing that. The seal could possibly be the fix but no way without driving or checking things. You could also see what codes you might find. Fuel Injection Technical Library » How To Run a Self-Test

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Bert