car stops when I take my foot off the gas pedal
Does it sputter and die when you take your foot off the gas (like it's having the fuel restricted), or stop immediately (more electrical-like, as if you flicked a switch)? You don't mention anything you've tried to fix the problem, but the first thing I'd try would be changing the fuel filter, and then maybe adding a bottle of fuel injector cleaner to a tank of gas and see if that helps. Another thing that might be the problem could be your catalytic converter; they tend to clog up over time and the symptoms are generally loss of power (it'll generally run, but not over say 35 MPH, and then not very smoothly).
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