M1028 revs up on it's own when cold, doesn't respond to throttle, then stalls...

[shotty]

Usually when I start my truck in the mornings, and only in the mornings, after idling for a few seconds it will rev up a bit and stop responding to throttle input. After a couple seconds it will usually stall as well. If I rev it a bit right after starting, it usually won't do this. It also does not do this during the day when its warmer out.

I'm guessing something in the IP is sticking when cold? Other than this issue the truck starts and runs great. I plan on dropping the IP off for rebuild but don't have the time/money at the moment. Thoughts?

Edit: I should add that when it revs up, it's not hitting the limiter or anything, its just a few hundred RPM higher, enough to cruise at 15 or 20mph

 

[Barrman]

You could have a leaking fuel filter base. The engine starts on what is in the pump, revs up a bit as it runs out and then dies. Holdng a faster idle gets new fuel pumped in before it runs out. Very common problem.

Before you spend the money on a new IP. Get a new square fuel filter base or convert to a spin on filter. It really could be your IP, but it might not. Putting a clear return line on the IP and watching for bubbles when this happens is a good way to figure out which it is.

 

[tony2wd]

Check the return line check ball on top of IP. If it gets clogged it acts like you described. Atleast on mine it did. Rebuild shop said governor was breaking down and clogging it. You can push the ball all the way out to get you buy for awhile.