All,

We have a 2009 Accord EX-L V6 with about 220K miles that had the engine replaced with a used engine (90K miles on the replacement engine) about a year ago. Earlier this year, we started seeing intermittent P0430 (Cat errors). Cats are expensive, so we've been putting off the inevitable replacement.

Recently the car started throwing an intermittent P0302 (misfire cyl 2) error. It throws the error only at start, but car runs fine for hundreds of miles. No issues with performance, misfires, lagging, etc. Runs great. Clear the error, and it come back a day or two later....

Trying to determine if we have a misfire issue due to the cats, or some other issue. The plugs were swapped new when the engine was swapped last year, and I just swapped out the coil on cyl 2 last week, but the P0302 has returned.

Any suggestions for next steps on the P0302 error?

Thanks

Tim