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Q: Engine code P0430 and losing oil

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What exactly does engine light code P0430 mean?

Also I'm losing oil but nothing noticeable when idle. Maybe it's burning up or coming out the exhaust while I'm driving?

My car has 114000 miles.
My car has an automatic transmission.

Diagnostic Trouble Code P0430 means that the ECU is detecting below threshold performance from the catalytic converter. The ECU monitors the catalytic converter closely and when a low performance threshold is detected the Check Engine Light will be displayed on the dashboard. Although it is possible the catalytic converter itself is faulty, there are many other possible causes of the low efficiency that must be ruled out first, including engine misfire, fuel injector leakage, engine mechanical damage, oxygen sensors that output out of range values, and exhaust leaks.


Oil leaks can be external or internal. Internal oil leaks often occur at the valve stem oil seals and/or the valve guides as well as at worn piston rings. External leaks could occur at spark plug tube seals, the PCV grommet, oil pressure sensor, crankshaft seals, oil pan seal, head gasket, and so forth. Oil leaks should be repaired because leaking oil can damage external engine components such as rubber motor mounts. If you want the source of all oil leaks identified and the repair estimated, simply request an oil leak diagnostic. If you have further questions or concerns, do not hesitate to re-contact YourMechanic.

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