TYPE OF STUTTER/STUMBLE
Steady throttle/Increasing throttle/Both: highway speed crusing
MODS
Intake: K&N Panel filter
Exhaust: catless up, OEM Down, Catback
Fuel: Stock fueling, 93 octane
Turbo: VF40
Engine Management: Cobb OTS Stage 1 91
Tuner and revision of tune(if you don't mind):
MAINTENANCE
Sensors changed: none, going to clean MAF
Plugs changed: went 1 step colder
Coil Packs changed: changed all last year
OTHER SYMPTOMS
Check Engine Light: none
Etc: Bad idle at times, not always and at differing amounts of shaking
RESULTS
What has and hasn't worked for you: filled it up with fresh gas, didnt come back for 10 miles. also had a bad idle that comes and goes.
If something worked, how long has it been working for:
any idea at what the problem could be?