Car lopping while stopped at a light, made a rattling sound, emitted a foul sulphur smell and check engine light came on. The car chugged along for a couple of blocks until I could park and shut it off. When restarting it idled so roughly that the engine literally moved about and the smell was still there.
The code shown when read at this time was P0300. Plugs, wire, coil, fuel filter, throttle control module all replaced. Ran better, idled fine, but there was a rattling sound when first started and at idle and then the check engine light came on again after a few miles. This time P0420 code.
Replaced catalytic converter and muffler. Ran fine for a few miles, then check engine light came back on with P0420 code again. Now car runs fine, except when coming to a stop after highway driving there is a hot smell (temp gauge is fine) and the car will chug down when stopped after driving at highway speeds.
Where do we go from here??
Same issue with Throttle Positioner being dirty or worn in conjunction with the Mass Air Flow Sensor failure. There were conflicting error codes when the check engine light came on causing me to change both components at the same time.