Throttle flat spot

[Corey Jackson]

Hey, I seem to have a flat spot under light acceleration. It causes my truck to surge frequently under light load. Way more noticeble when MDS is on. Throttle body or gas pedal replacement is my question...
First 2 pulls on graph are hard pedal down, next 2 are gradual pedal downs. See attached pic. Any help would be Awesome!

 

[pt1655]

Sounds like you're experiencing throttle lag. Our trucks have fly-by-wire gas pedals; a sensor at the gas pedal sees how much pressure you are using on the gas pedal and adjusts the throttle electronically with a 1 second or more delay built in. There are 2 ways we all take care of that throttle lag; either a tuner such as Bullydog or Diablo, etc, or a throttle booster. Neither are cheap but both methods work quite well and make the engine so much more responsive and smoother. I have a Bullydog tuner and a Sprint throttle booster set to 50% or 1/2 second delay. I tried the 100% setting or no delay and I felt it was too touchy. In any case, the Bullydog Gt tuner I have didn't offer a throttle delay setting, the newer Bullydog BDX might offer it. Those who have SCT or Diablo or Trinity tuners have that option and they are quite pleased with the results. A lot of us with tuners also turn off the MDS as I have and really enjoy a smoother running engine and I have yet to see any difference in gas mileage (I would on the highway if I didn't have my camper shell and heavy BF Goodrichs KO 2's). Good luck

 

[Corey Jackson]

It hasn't always done this. It' a new problem. It' more of a drop in voltage rather than a delay in response. And it' always in the same throttle position.

 

[rotwiler]

Have you cleaned the throttle body? Just did mine and made nice difference. My neighbor has a 2012 5.7 and cleaned his due to stumple from idle and cured it. First I would try throttle body and clean pcv or change and possibly spark plugs.

 

[Pull Ya]

Pedal Commander
Jay

 

[Corey Jackson]

Pedal Commander
Jay

?? What' a pedal commander?

 

[Pull Ya]

Let me do a quick search for a couple of threads that fully explain the PC and I'll post them in a minute or two
Jay

 

[Pull Ya]

http://www.ramforum.com/threads/pedal-commander.116951/
http://www.ramforum.com/threads/pedal-commander.115523/

This is just a couple of the threads--there are about 25+ threads talking about it. Do a search under Pedal Commander in the Engine and Performance section.
Jay

 

[Corey Jackson]

http://www.ramforum.com/threads/pedal-commander.116951/
http://www.ramforum.com/threads/pedal-commander.115523/

This is just a couple of the threads--there are about 25+ threads talking about it. Do a search under Pedal Commander in the Engine and Performance section.
Jay

Ya, that's not going to solve my issue. But thanks for the info.

 

[rotwiler]

I just did my throttle body and plugs, immediately after cleaning throttle body I felt a gain from it, more responsive and smoother and my truck has 40k original miles. Then week later did plugs and felt a difference again, made truck more responsive, Also before cleaning TB and plugs, mds would vibrate more when coming on, now is much better. My plugs looked great, but glad I changed them, my mpg went up over 2mpg. Throttle body takes 15 minutes to remove and clean with brake cleaner, easy thing to try. Also a alternative to the peddle commander is a 9-drive, does basically same thing for around $70, but don't think its your issue. I would try throttle body first and throw some redline fuel cleaner in a tank or gumout complete fuel system cleaner, I always felt difference after running those after about 1/2 to 3/4 tank.