Truck starts hard, runs for a few minutes then shuts off?

Hi,

The pressure is slightly low. It should be between 60 and 66 PSI with the key on and the engine off. See pic 1.

The idea that it drops but doesn't stop sounds like there is some kind of restriction. Did you replace the fuel filter? Was the sock at the bottom of the pump clean and in good condition?

Yes, to your question. If the pressure doesn't drop, there are no leaks.

When the engine stalls, does it start right back up? Also, when the fuel pressure drops, does it go right back up when you turn the key off and back on?

Let me know.

Joe

I replaced the fuel pump because it had failed about a year ago and the fuel filter was replaced then. When it failed again just recently, I did not replace the filter, I thought it was new enough. After stalling it does not start right back up. When I cycle the key, it seems that the pump stops working for a bit because I get zero pressure on the gauge. Then after a bit it starts again. Almost like it’s overheating.

Hi,

Have you checked the fuel pump relay? If there is no pressure and you need to wait, it may have failed.

The relay is in the under-hood fuse box. See pic below

Also, I need you to check something for me. When it stalls and you have to wait for it to start, see if it will start if you use starting fluid. If it does and then stalls, we can confirm a fuel issue. If there is no change, check to see if there is spark to the plugs.

Here is a link you may find helpful:

https://www.2carpros.com/articles/how-to-check-for-ignition-spark

I'm suggesting this because if there is no ignition, the fuel pump is shut down to prevent flooding. If there is no spark, you'll have no ignition or fuel. If that is the case, we may have a loss of spark.

If you have a live data scan tool, when cranking the engine (no start condition) see if there is an RPM signal on the scanner.

Let me know.

Joe

See pic below.