Sounds like you may need a good tune-up... How many miles on the car?? Ever done a UIM/LIM (upper/lower intake manifold) rebuild?? That carbon really does build up. That would definitely help. I know that my dad's ranger will ping with certain brands of 87 octane. Its always done it though. Could be just poor quality fuel...
1999 Mystique LS V6
Alpine CDA-9807, Rear deck sub, Opt. TB, K&N RU-3530/MAF adaptor, custom heatshield, FSVT 17's, SCT 4-program chip, Eibach's/ST200's, Hella Fogs...
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