Friend of mine has a 93 5.8 f-150 that sometimes won't restart when it's hot. Has to wait 30-60min for it to fire back up.

Shops can't seem to figure it out. New fuel pump last year, still does it.

She says it's only when it's hot, and hot outside. It doesn't do it in the winter. (Which in AZ isn't very cold)

I'm not too familiar with this generation, so I don't know what it all has. I'm thinking it could be a bad MAF, or a sensor of some sort.

What say you?

 

Also, it will sometimes die while driving, but mostly just won't restart.

 

When you say, "restart." What does it do exactly? Does the engine turn over and just does not start?

Other then checking for codes.

Once you warm it up to cause a no crank issue. I would check to see if its getting fire to the distributor when your trying to crank it. It really sounds like some sort of ignition issue in my opinion.

I'm not an expert maybe some one else will chime in.

 

No codes

She says it cranks but won't fire up. I haven't experienced it myself so I'm in the dark too.

 

Very common problem on these trucks. Unfortunately there are two main causes. First is the PIP sensor (aka stator) inside the distributor fails when it warms up. Typically you will get an error code for it, erratic PIP signal. But that is not always the case. Second common failure is the Ignition Control Module ( ICM ) located on the driver side inner fender. It's grey in color and mounted to a heat sink.

The PIP provides the signal pulses for the ICM and computer. So it's a matter of figuring out which one is bad. A few write ups can be found here and the web. On my phone so my links are not handy right now.

 

Ok well she says they checked the ignition module and it was fine, so the PIP could definitely be the culprit.

 

Verify they checked the ICM multiple times. Once or twice may not be enough.

For reference on the PIP aka stator: Stator

Some good info here: Part 1 -How to Test the Ford Ignition Control Module (Fender Mounted)

 

Mines did that a few weeks ago my clutch fan went out and I changed the pickup coil and its been running fine..

 

Here's a good video showing how to check the PIP/stator signal. Top wire in the ICM connector I believe.