My powerjoke I had was really wierd about the throtle position. If you only went about 3/4 throtle it would pull 100%harder than at wide open throtle. I thought that the cummins wouldnt be that way but it seems to be worse. It pulls hard at half throtle but you can mash it up to full throttle and it falls on its face? Why is this. It only has 5,000 miles on it. Can the supply pump not keep up with demand? This really sucks.

 

My guess would be it is de-fueling the engine by the computer to save the engine from high EGT 's . A diesel unlike a gas engine if you add more fuel more heat is created . I would think that it looks at your speed and your throttle request and shuts down the fuel to save the engine from damage . Hopefully others will chime in and correct me if I am wrong .

 

Since these trucks use fly by wire a recalibration maybe needed for the throttle position sensor. Disconnect both batteries for about 15 minutes, reconnect and turn the ignition key to the "ON" position (do not start the engine) and slowly press the throttle all the way down until it stops, release the throttle and turn the ignition key to the "OFF" position. Now start the engine like you normally would.

MikeyB

 

Mine does the exact same thing since I bought it. I was thinking of replacing the TPS this weekend and see if that was the cause. I will try this recalibration first. Thanks for the tip.

 

Yep, most likely Throttle Position Sensor. Mine was like this for the first year I had it only the other way. I could never get full throttle or kick down. Turned out that full throttle was matted to the floor and I had added rubber chexplate floor mats. Once the TPS was reset for full throttle at 7/8 pedal stroke, I didn't have to mash my foot to the floor to get power. Of course I had it reset when I was installing the TST. Double whammy good!!! ks

 

How did you reset it?

 

Something I have noticed is that if you go halfway you keep it in OD. For passing and such the higher gear will suck you back in the seat build up speed very quickly. If you put it all the way down, it will kick down to 3rd, and the gear ratio will hold it back. It may be making power, but it is making it slower.

Nevermind, you are running a 6 speed.

 

Hoehand, The instructions were given above once again. ks
Since these trucks use fly by wire a recalibration maybe needed for the throttle position sensor. Disconnect both batteries for about 15 minutes, reconnect and turn the ignition key to the "ON" position (do not start the engine) and slowly press the throttle all the way down until it stops, release the throttle and turn the ignition key to the "OFF" position. Now start the engine like you normally would.

MikeyB