[Dirty Sanchez]

I have a 06 GT, made in late febuary. At part throttle (cruising on the highway maintaining speed) i get a slight jerking (not violent), if i give it more gas, its fine, let off the gas and its fine. Its right at the mark where you maintain speed. Mods are JLT2 CAI, Xcal 2 tuned from brenspeed, Steeda UDP and Steeda CMDP. After getting parts installed and flashed, ran GREAT. two weeks later took it to the dyno, everything looked great, lowered the timing from 26 to 21 and adjusted faul to maintain 12.5 ratio. Leave th4e dyno running HARD, not a single complaint. 2 months go by, i dont change anything, all of a suden one day i noticed this stuttering at part throttle. I do the normal, re-load tune, no diffrencce, laod Brenspeed tune, still no diffrence. CHanged gas companies and pump (92BP ive always used, 92 BP from a diffrent gas station, 91 Conoco, and 91 amaco), still no change. Checked Wires and plugs: nothing stands out (though not sure how to check these, plugs looked a normal worn plug (not singed, no rainbow effect, no tar like look, not black)).

I dont have a fuel pressure gauge or have an idea how to check this while the car is moving (at idle it seems fine). Can anyone help. I cant find a TSB that fits my description. I dont want to rip the mods off to take it to my anal delaership, as sson as they see one modded part, they will instantly blame it on mods and charge me 200 bucks to look at it.

i could really use some help right now. car has 2k miles on it, never raced, never did a burnout, just occasionally will wrap out a gear or two on a weekend.

Thanks,


DS

btw - very cool site, not sure how i never heard of it before now (been building up mustangs for 10 years now).

[Drgnracin72]

its a pretty new site only been around a little over a year now. as for the tune, i would send the tune back to brenspeed and have them go over it to make sure everyhting is ok. ohter than something in the tune, i dont really know what it could be

[mdvaldosta]

What kind of air filter? Maybe oil / dirt on the MAF, something loose around that area, vacuum leak maybe. Really sounds like it's something to do with air metering.

[99mustang232]

i would take that money that you would be spending at the dealership and put it on the dyno and get it tuned, they will be able to monitor the air/fuel and review and modify the settings as needed.

[Dirty Sanchez]

i will check the MAF, what should i clean it with? I sprayed Carb cleaner around the intake and CAI seals to see if the idle changed, nothing. Dont think it is a leak anywhere. Air filter looks brand new (only used for about 1k miles). I thoguht it was the tune, but after loading 2 diffrent tunes, figured that should be fine. Like i said i had it on a dyno after installing the parts and loading the tune, everything was fine. Not sure how the tune woudl have changed itself 2 months after loading it and dyno testing it.

Thanks for the help, keep the suggestions comming.

[Dirty Sanchez]

Turned out to be a fualty TPS, easy fix and im back on the road, no more issues. Thanks for the help guys. Hope this helps anyone having similiar issues.