2001 duramax falls flat when under power,will come back if you let up ,acts like its running out of fuel , whats wrong, it has 234000 miles thanks tom

2001 duramax falls flat when under power,will come back if you let up ,acts like its running out of fuel , whats wrong, it has 234000 miles thanks tom

Assume no check engine lite since you didn't mention one...

How many miles on your fuel filter? Sounds like its starting to be restricted. Depending on whether you live in cold climate, you may have a fuel gelling or fuel filter icing problem

Start by replacing fuel filter. Make sure there is no restriction in fuel system (ice in fuel tank) you will know if you can't prime new fuel filter with primer pump.

I had similar problem on an 02, I had a lift pump and brand new injectors. I hooked up a vac/press. gauge to the service port in front and duct taped it to the brush guard and even with 10 psi or better at pump it still fell on it's face. I then drove around with scan tool and watched rail press. , commanded vs. actual. whenever i got past 3/4 throttle desired went up and actual fell and the truck would go flat until I lifted. I ended up shipping my cp3 to Industrial injection and it turned out it was shot! moral of the story is get a scan tool, get GM to give you new injectors and make sure you have good fuel supply and if that doesn't fix it, then you might be buying a new CP3. By the way it had 116,000 miles on it when this happened.

no check engine lites, truck is in wisconsin about 20 degrees, truck came from down south

no check engine lites, truck is in wisconsin about 20 degrees, truck came from down south

20 degrees should not be a fuel problem, but I am south of you and it's been a heck of a lot colder than 20...

Are you running any anti-gel fuel additive? If not, you might try doing so at least when temps are expected to be below freezing