2001Pontiac grand prix gt 3800 motor chugs after it gets warm. put fule injector cleaner in it changed air flow sensor and throttle postion sensor new plug wires . does anyone have a clue what it ma.
That's a pretty vague description of the problem so its hard to say. Check for codes to see what the car is telling you. Also could be a plugged catalytic converter. Any muffler shop can diagnose that for you. Remove it if its legal to do that where you live, otherwise you will need a new one.
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