On most higher performance trucks or even stockers this can happen and this is a simple fix i figured out, and many other have but i havent seen a post on it so i will give this a shot.

In the past i have read about 12 valves having issues with bucking and being really hard to drive, i didnt beleive this untill i had my own 12 valve, after i had done the 4k GSK the throttle became EXTREMELY TOUCHY!!!! if i even bumped pedal it was almost immediate whiplash.

As i made my truck faster i noticed it was getting worse and worse at "bucking", it got to a point where i had to baby it or go full throttle to avoid the "bucking". At midrange i could barely hold the throttle cause it was bucking so hard i would have to let off or go full throttle to make it stop.

finally i had enough and started looking around on the throttle mechanism to find out how to make it stop bucking, and this is what i came up with.

there is a small spring just under the throttle cable that returns the throttle to idle, where the spring is hooked up from the factory it dosent do a very good job of holding the throttle back, so i pulled the spring out of where is was originally and pulled it up to a smallish hole higher on the throttle mechanism. a diesel mechanic told me there was soposed to be a spring there, so if your spring is already there i recomend not messing with it unless you want a broken neck/driveshaft

its kinda hard to explain but it solved my bucking problem, i have to purposly romp on the throttle to make it buck now!!!

i will try to post a picture of it some time soon

 

thanks mine is so touchy i let a friend drive it up my drive way and he stalled it out when he went to take off and it auto..

 

so if the spring is there what do you do? you do mean if the spring is in the hole you changed it to already?

 

ever get the pics?

 

Going to have to check it out.

 

wow, this is an old one, oh and never got the pictures up. i will try sometime....

if its still touchy even after you moved the spring, go your local parts dealer and get a tougher spring(generic ones will do just fine) and replace the factory one. one thing to remember is when you make your new spring, make shure its good and tight, mine fell off and my truck ran away full throttle...