I know the code has to do something with the catalytic converter but does that also cause it to idle so high. It kills my gas. And is their anyway to fix the problem without having to buy a new catalytic converter.
My car has 170000 miles.
My car has a manual transmission.
There are a number of things that code P0420 relates to, most of which will directly or indirectly affect the performance of the catalytic converter. This may be caused by a faulty oxygen sensor, fuel injector leaks, faulty spark plugs, ignition time problems or an intake air leak. The high idle you describe may point to an intake air leak which can also contribute to this code being triggered as this will cause a lean fuel condition which results in too much oxygen being present in the exhaust gases. I would suggest having an expert from YourMechanic come to your location to diagnose and inspect your car.
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