2007 EX 4-cyl.

Thanks!

 

I deleted your duplicate post. Read forum rules.

I have only one experience w/ a aftermarket catalytic converter, Eastern. I bought for 1999 Subaru Forester w/ code P0420 and oscillating secondary O2 sensor voltage.

Installation was difficult at there was a redundant O2 sensor bung on the cat that had to be plugged (probably for other model Subarus). The only plug I could find was a spark plug that I had to shorten to fit. Converter worked OK for about 1.5 yrs and then I got same code again. Not sure if this indicates a Subaru fault or converter fault.

Suggest going to Amazon and reading the reviews for some guidance on quality and fit. I checked and there are a number of reviews.

good luck

 

Apologies, I thought I may have not posted it by accident.

I did try an aftermarket cat, but just like yours it threw a code again about 2 years later.

 

Why do any catalytic converters fail to continue functioning? It's one thing to have a failure due to overheating of converter from excess gas flow (leaking injector, etc), but frequently converters fail w/o any apparent reason or engine fault. I've heard possible explanations of engine coolant contamination, gasket/sealant contamination but no convincing explanation for these random failures.

It may be that aftermarket converters don't last as long, but that is also an unknown.

In your case, there may be an underlying problem such as long term coolant leakage. Supposedly the coolant has contaminants that poison the catalysts. Any long term coolant use?

good luck

 

Oil vapor routed through the combustion chamber via the PCV system (and to an even greater degree in engines which "burn" oil) has also been fingered as a contaminate for catalytic converters; as related to me, failures occur most often when the engine is lubricated with conventional oil, which by definition isn't as stable as synthetic.

 

Following video offers some good information:


good luck