Hey guys...

Its been awhile since I last posted but i'm just getting back into my honda..

Got my license about a month ago, and my moms been driving my car back and to work.

But anyway..

Last June I had a Catalytic Converter installed. Since then, had no problems.. cept a rear main seal oil leak, but thats irrelevant. Tuesday of last week, I had a Check Engine Light come on. I took it to my mechanic on wednesday and the code was pulled. 420, Cat going bad.

So I thought that was kinda wierd, just got it 10 months prior, so I had it diagnostic'd and they said cat was going bad, and an O2 sensor was bad.

Wouldn't I get a CEL if the o2 sensor was bad, or going bad?

And where would I be able to get one?

 

The O2 sensor may be fine but there is a leak in the exhaust manifold. In this case, the O2 sensor would erroneously signal the ECU to increase the amount of fuel in the cylinder, and this rich condition would destroy the catalytic converter.

Alternatively, in some cases, a faulty O2 sensor is not recognized by the CEL/ECU system.

 

couldn't have said any better, that about sums it all up. yes

 

So....

All of a sudden the CEL just goes out.. I don't have a Check engine light anymore.. Why would it all of a sudden turn off?

Like I said, code was pulled and the cat was under threshold, and now a week or so later, it turns off.. ?

 

Well, just clear the code from the ECU and hope the CEL doesn't return. If it does, pull the code again to verify that it is the same one as earlier. Sometimes problems are intermittent.