So I heard a while back that the TSTs with the rail pressure option would or could cause your truck to surge under low to moderat throttle. My truck had that surge but it wasnt a big deal to me I would just shift gears and it would quit.

Well I finally unplugged my tst from the rail sensor and ta da, no more surge. I have a smarty with pressure so I dont need any more pressure but I also have an mp8 just in case I did and I had the mp8 before the smarty.

The only reason I ever had the TST hooked into my rail sensor was just to compare the RP on my tst with the dipricol guage.

I have had the truck surge slightly once since I unplugged the tst from the rail sensor, but I am not sure why, maybe smarty, maybe a coinsidence. But the surge (befor I fixed it) was most pronounced when it was could out and the truck was cold.

I have duplucated the situations that would cause my truck to surge and it seems to be gone.

Just an FYI, maybe this will help somebody out.