Engine/Transmission (1994 - 1998) 96 12valve interminetly loping at idle

[moparmafia1998]

Having issues with my 97 12 valve. I have checked the fuel pressure and it is good, check all hoses all a fairly new. This only happens at idle otherwise runs like it should. It will idle and then just start loping like it has a big cam. i can tap the throttle and it will stop but i can also tap the throttle to make it start loping. Idle is set at 850. I can also crack the injector lines and will stop to. Please help. Have had diesels for awhile but just joined the site and i love it!

 

[Missouri Mule]

Try adjusting your valves!

 

[moparmafia1998]

ill give it a shot this weekend. Its been over 100 all week here. thanks

 

[RCorbeil]

Does your pump hsve a buffer screw? If so loosen lock screw nut and turn in 1/4 turn and retighten lock nut.

 

[moparmafia1998]

buffer screw? Not familiar with that? Where would that be? Willing to try anything

 

[rrl989]

Could a vacuum leak cause this ?