I need some assistance in diagnosing a hesitation / misfire issue I am experiencing. car is a 2007 mustang gt with jltII / xcal3 / flowmasters.
anyway, the emissions warning light came on the other day (blinking) which according to the manual references a misfire. i thought maybe i had some bad gas in the car, as i was low (2 gallons or so) so i filled it back up and drove it a few more days without incident.
i since took a 900 mile roundtrip to niagara falls and had numerous times where the car would hesitate, and sound different at highway speeds. the emissions code light came on only once out of the numerous times i felt the hesitation. it does not seem to be regular, or happen at any speed. i h ave felt it at low speeds and high speeds, but more at highway speeds.
any thoughts as to what i might be dealing with.
spark plugs (havent had a chance to pull any and look yet)
clogged fuel filter?
anything else i can check myself?
any help would be appreciated.