Hi. When I try to start my 2500HD, it cranks and cranks but won't fire up. When I switch the ignition back off and then restart it, it starts right up and runs great. No bogging or anything. If I stop somewhere and then come back to the truck after a few minutes, it will start right up. Other times it does the same crank-forever, switch off, restart and then runs great. For a few days straight, it would just start right up first try. Engine always runs great after it starts. Any ideas? Thanks!

 

I have the exact same problem with 02' 1500. It is annoying as hell. I replaced the starter with no results. If you get any ideas please pass them on.

 

When you first turn your key to the on position do you hear your fuel pump for 2-3 seconds?

 

When I turn my key to the "ON" position I do hear my fuel pump kick on. I have tried to go out when the truck is cold, turn the key to "ON" and wait a few seconds but got the same result. It just turned but wouldn't turn over until I turned the key back to off, then start again.

 

I would say it is probably fuel related, either a partially clogged fuel filter, faulty pressure regulator, or the pump is losing it's prime when sitting for a while (thats the reason it will start back up when it has only been sitting for a short period). I would connect a fuel pressure guage to it and do a leak down test. See how low the pressure gets when the truck sits for a while. Also unplug the vacuum line that goes to the pressure regulator and see if there is gas in there. If so, that is your problem. It should not have gas in the vacuum line.

 

Good stuff, I'll check those. Thanks! Good luck with yours too, inflight.

 

could also be an injector bleeding down.....my 97 suburban does the same thing so I just turn it on then off then start it...the cause is a loss of pressure in the fuel system....the EVAP system can also cause this