My hesitation started again yesterday on the way home, then this morning it will hardly run. Idles fine, more than 1/4 throttle is fine, there is nothing in between. Sputters, backfires, cuts off all together if you hold a steady light throttle. Only way you can drive it is to accellerate til you catch up with someone, back off completely and drop back, then do it again. Checked for codes, none, re-adjusted tps, checked tps through the whole range, checked all connectors, etc. Nothing seems amiss. Never had any hesitation till I had it re-mapped at the dealer. since then it has been on again-off again. Will run ok for about a week after doing the 12 min. tune. Never had anything as bad as this. Very dangerous to drive.