My GT has ran great up to about 3 months ago, it started hesitating slightly which eventually got worse. I changed the sparks plug and the problem stopped. Then a month after that it started again but even worse, well after inspection of the spark plugs i noticed oil on the tip, i changed the coil pack, The hesitation went away for the most part, but there is still a slight hesitation and im still not getting my power and the response when i punch it is not good at all. What other routine maintenance should i try...I have a fuel filter but have not yet installed it. Im thinking maybe i should try changing all the coil packs but there not cheap..And i would need 7 more.so im hoping its something else. The engine has 150,000 (mainly highway) miles. Ive never had any problems till recently. Thanks in advance guys!
04' mustang 3.9 40th Anniversary Edition- (V2 Vortech Supercharger, 38# injectors, 3.73 gears w/ T-lok, Predator Diablo, Mac cold air intake, Port & polished upper AND lower intake manifold, Mac Long Tube Headers, Mac o/r H pipe, flowmasters, 2.5 flowmaster tips)
03' Mustang GT (20" Cobra R's, 40 series Flowmasters)