So a few months ago, my try out engine set alight came on. I took it to a random mechanic, he said he scanned it using two uncommon scanners, both charitable him uncommon codes, but the one run of the mill code they both gave him was for the catalytic converter.

He reset the try out engine indicator, and it came back on again with 30 miles. But in view of the fact that then, it has been off most of the time, but comes back on irregularly. Any encounter with this, anyone? Or at smallest amount some educated speculation?