Engine breaks up at 2300 rpms

[NDanecker]

This just started to happen. It happens most freqently in 3rd gear on heavy accel at about 2300 rpms. Sometimes 2100 ... . 2400 but really only noticable on heavy accel. Almost seems like its being starved for fuel.

I changed the fuel filter approx 1k miles ago so don't think its that.

Any ideas??? Bad injectors? How can ya tell? (I do NOT want to visit a dealer... ... they all *&^*()

 

[rbattelle]

Lift pump not keeping up with demand? Just a guess...



-Ryan

 

[NDanecker]

That does sound possible. Any way to test it? And wouldn't a low pressure throw a code?

 

[rbattelle]

A low pressure from the lift pump would not throw a code... there's no sensor to detect it. The only thing that will throw a code from the lift pump is a low voltage signal, which doesn't help you. The only way to test the pump would be to either install a FP gauge or do a flow rate test. The powertrain manual calls for a flow rate test (38 GPH is minimum required flow).



-Ryan

 

[6 2 Carl]

This just started to happen. It happens most freqently in 3rd gear on heavy accel at about 2300 rpms. Sometimes 2100 ... . 2400 but really only noticable on heavy accel. Almost seems like its being starved for fuel.



QUOTE]



I had the identical problem with my truck, and it turns out my lift pump was getting weak. After a month wait my dealership finally got a pump and replaced it. Truck runs better than ever now. Adding a Fass or AirDog is now my top priority when it warms up.



Carl