Have you ran the codes on it?? I had a problem just like this on my T-Bird and it ended up being the max air sensor. If you figure out it is not any of your ignition my bet would be on a bad sensor somewhere.
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88GT 5-speed
Mods: Cervinis Ram air hood 3.73 gears, King Cobra clutch, Pro 5.0, March alum. Pullies, DynoMax Cat-back, WMS Xtrac subframes, 16" Ponies.
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