What could be wrong?
Run the codes, it could be a VSS fault, without that signal the computer is guessing at the speed you are traveling and having difficulty setting timing and fuel mixtures.
P0460 and p0500 are the codes if that says much
P0460 Fuel Level Sensor Circuit Malfunction P0500 Vehicle Speed Sensor Malfunction So here it is a VSS code P0500, so check snd make sure it is plugged in at the tranny, if it is then you can take a chance and replace the VSS or have the wiring tested at a shop or you can ohm it out your self from the ECM to the sensor on both wires. If your not concerned about the fuel level light I would not be concerned about the P0460 code at present.
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