check engine light comes on, cruise control light flashes.

Question

I get a p0420 code and the cruise light flashes. Subaru dealer said the catalytic convertor was bad(someone before me had changed it). Didn't quite believe it, but had it changed again, not by subaru(they wanted $3000). Lights came on again after about fifty miles. Not sure where to go now. Thinking ECM maybe? Or bad wiring? I get the same p0420 code occasionally on my 2003 Outback but cruise light does not flash. Any thoughts? Thanks, Bruce.

Answer 1

HI there

This could be the result of the aftermarket converter or an issue with the rear O2 sensor. These cars in particular are very sensitive when it comes to the converters. 

P0420 SUBARU - Catalyst System Efficiency Below Threshold

Read more: https://www.autocodes.com/p0420_subaru.html