99gtstang

ive got a 99 gt.... minor mods... x pipe, pullies and intake... its been misfiring/skipping... car drives almost like a coil pack is bad.. it wants to stutter at low rpms and ... while driving hwy it may stutter every now and then...boots, springs, and plugs are new.. when i replaced plugs it quit for about 70 miles... when i throw alot of fuel injector cleaner in it, it quits or slows down..... no light is coming on neeeeeeeed helppppp

GoldenChild

um...i dunno man, the best advice i can give is, u might wanna leave this one up to a mechanic or ford, see what they say is the prob. and go from there, if they look at it your not having them fix it right away, just let them analyze the situation? just a thought

good luck

99gtstang

trying to avoid hearing that YOU NEED TO SPEND A BOAT LOAD OF MONEY... problaby drop it at ford... 80 for diagnostics........ thanks

Boostaddict

Tune maybe!! Have you datalogged the car to check its statistics? After raplacing the plugs and such and if you have some fresh gas in there and its still doing that I would guess it could be the tune. Let me know if there's anything else we can do to help you out. Thanks, Jared

yellowjacket01

also,maybe that your mods are slightly affecting your timing

99gtstang

no i have not and i have no idea what that is to be honest....... last week i drove until gas light came on... put about 8 ounces of lucas fuel treament and 1 gallon of gas... ran perfect.... gas light came on.... drove 15 more miles to run tank completely out.. filled up 93 at QT started right back up... can you give me more info on TUNE?

99gtstang

ran like that the day i bought it and the check engine light came on # 5 cylinder so i replaced coil pack ran good for 200 miles......... but the day i bought i put the x pipe no cats. and 40 series flowmasters.....and the crappy bbk eliminators.. that dont work like advertised..


next Q

can my timing chain be stretched? maybe cam caps loose not causing valves to shut properly... becuase car wants to do it bad under a load... up hill or low rpms....car has 109K on it... and i have only had it a few months...but i thought i got a deal.. for it... non stop probs....traded a 00 xterra with 155K on it and 1k cash for the mustang...with 104K on it..

sweet99

I just bought a '99 last mopnth and had a terrible shudder especially when it went into OD/lock-up at low speeds. Tried injector cleaner, changed the tranny fluid and filter. Even took it to a tranny shop. Hope you guessed I have an automatic by now! Tranny mechanic said the tranny was fine and it was electrical. I went and bought 2 coils at the local pick-n-pull and that was it. Mine was easier to diagnose as I has one generic coil on it and that is the one I changed but my symptoms were similar to yours. What octane are you using? Isn't that Lucas product an octane booster or do they have another product? Their booster actually works. Hmm maybe you did mention octane. My car did not trip the service engine light either and man it should have as it was rocking the car violently at low speeds(35MPH). Mark
Why run 93 unless you have a Cobra 87 octane is fine. ot saying the higher octane is causibg the trouble but it may not be necessary.

99gtstang

always ran 93 in all my cars... maybe i could try... 87 and see what happens..... im an kind of leaning towards......coil packs.. i just checked the ohm resistance thats my next post....

04BlueGT

Granatelli makes coils that are supposed to be 200% better than stock. You should look into those. Be warned, they are pricey.