I have has the truck for about 4 months now. I installed a 366 spring and turned in the fuel screw and adjusted the fuel pin to the deepest side and turned the star wheel a little. It has been idling fine up until about a week ago. It idles up and down just a little bit while in park. when I am driving and coning to some traffic where I just have my foot barely on the pedal it will start to lope like it has a hot cam. It also will lope if im in park and I just bump it off of idle it will lope for a little and then high idle like it should. I searched and found the loping thing might be air geting into the system from one of the lines fuel filter ect. for the idle up and down I read maybe it could be a broken top hat spring? any input would be great thanks Fred

 

Mine would actually drop below an idle when I let off sharply. Are you running Bio? I've been running regular ULSD with some conditioner. Seems the extra lubricity helps the sticky governor linkage.

 

Ive been running fuel from the pump since this has started with 2 stroke in it before I was being a bad boy and running some fuel that was the same color as my truck... and as soon as I went to the pump this has started

 

Last night I took the pump top off and looked around. the Top has spring is fine my 366 spring looks like a 366 spring. there is just some thing that I am not catching could the start spring that they talk about in the ve operation be weak and causing a erratic idle and maybe a lope rite off of idle? Befor I took the pump top off I tried to adjust the idle and I almost backed the screw all the way out before obtaining a low enough idle then if i snaped the throttle it would rev back up to there it was and I would have to lightly move the throttle around to get it to go back down to idle.

 

It sounds like you have the throttle indexing out of whack.

 

really would that just make it start to do these weird things?

 

Yes, they don't idle right if they are indexed wrong.

 

Its just weird that it would start to do this 3 months after I had it apart.