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when i get up 55-60 mph the engine vibrates
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Have you checked your motor mounts? one might be loose or broken

also are you positive its your engine vibrating? I had a front wheel out of balance once that drove great till I hit 55/60 and it almost shook the fenders off...also pull a couple plugs and check them out, if it sputters "all the time" its probably not your wires but if their old I would replace them anyway...also could be a blocked fuel injector or a bad coil or fuel pump...It could also be as you think a fuel filter, if its the kind thats in your gas tank it will be a pain to check....Raddman Out...
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'I OWNED A NEW CAR ONCE, MY X WIFE LOVES IT'
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