850T has codes 231,443,435

Pauly · Post by **Pauly** » 26 May 2006, 21:30

I have had codes 231,443,435 return twice now after resetting the A2 socket. The car runs OK, although I suspect it may have a little less than normal acceleration.

From my research, it looks like I may have a bad front O2 sensor, or a bad CAT. How can I tell which is the problem?

Post by **MadeInJapan** » 26 May 2006, 22:03

Very very rare for the CAT to go. Anywhere after 100K miles it is common for the front 02 sensor to go. If you're at or over 100K, it would be worth replacing the front one anyway. A new one will net better mileage and pay for itself eventually anyway. http://www.autohausaz.com/ has had the front ones on sale (OEM made by Bosch with the correct connectors) for $95. I have one still sitting in a box from them I plan on installing when I have some time.