Surging at cold low throttle....

[06MonteSS]

well, as you mentioned yourself a few times in that post, the surging happens with the stock GM (original) tune as well...

so that's not a tune issue.... that's a "mechanical" issue...

I would restore the original backup (stock GM) tune, drive for a day, and then take it back to the dealer and explain the issue to them...

there's a problem with your truck, not the tune...

[Ill_Born_SS]

Hey Dave
Thankx for the clarification. Clean the TB and intake system yourself, the dealer will not do it manually, they will cut corners. It is not hard to do nor will it take to long.

As for the update on the predator ,yea it was released march 28 08, no biggie.

As recommended return the original tune, (clean the intake system as mentioned earlier) Then drive it normally for a few days.
Meanwhile I will put together a small list of things for you to check.

Also, get your cal IDs from the truck and then compare them to availabe IDs, verifing that all yours are current.

http://tis2web.service.gm.com/tis2web

If any are not up to date return to dealer for the update.

Don`t worry about doing a cruise log right yet! Lets figure out the main problem first.

[evadllig]

Thanks for all the input guys....

One point of clarification - the surging happened on the original factory tune. Since I had the dealer reflash the the truck and before I installed the Diablo tune it did not happen any more. It would seem that the original dealer tune had something to do with it. But I also agree that there may be other mechanical issues that are not helping.

I think I will defdinatly clean the throttle body myself. Probably good to learn somethng new anyways...

As of today I have the Diablo installed with a -5% LTFT and I have not had the problem for several days. I am going to keep monitoring it and see where it takes me....

Thanks Again.