Jaguar Repair Problems? Ask a Jaguar Repairs Expert.
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If the codes were P0420 and/or P0430 then it is 99% of the time a faulty converter. Depending on the warranty start date the cat converters can still be covered under the 8 year 80,000 mile emissions warranty. The P0420 is for the bank 1 (rear) cat and P0430 is for bank 2 (front) cat.