2001 2500 hd 8.1 stalls,sometimes starts right back up or let set for few minutes and starts changed fuel filter and added heat to gas for incase of water, starting to happen more frequentley. Fuel pump??

 

Get a fuel pressure gauge, and check the pressure in the rail. then see if its in spec. If not, replace pump.

 

checked pressure 55 psi inrail

 

is that spec in the book?

 

spec 50 to 60 psi

 

ok, so maybe timing? have you checked that? how about spark?

 

Did you check your fuel press running or with the key on? Sometimes they will hold pressurize the system then not be able to keep up.

 

My 5.7L Suburban did exactly the same thing -- would stall driving or idling, then start back after sitting for just a few seconds. It was the fuel pump. It would hold pressure for a while, then the pump would stall.

 

crank sensor

 

I would tend to agree with RonH; just having what was written so far to go by.
Normally a fualty crank sensor will almost always allow a restart.

I have seen fuel pressure regulators cause stalling as well if the diaphram becomes ruptured.