1995 850 t5. CEL on, codes 443 435. O2 sensor?

2012 · Post by **2012** » 25 Jan 2015, 09:54

My 850 T5 has 153000 miles and keeps getting codes 443 and 435 almost every couple days after I reset the light. What should I do to fix this problem? Replace 02 sensor? Anyone else fixed this issue? Thanks...

Post by **Ozark Lee** » 25 Jan 2015, 18:28

The 4-3-5 code is a front oxygen sensor, slow response, code and the 4-4-3 is a catalytic converter efficiency code which is generated by a reading from the rear oxygen sensor. The 4-4-3 could be getting thrown due to a problem with the front sensor reading since it compares the two values to arrive at an efficiency determination.

A vacuum leak can cause the 4-3-5 code as can bad compression but if those two things check out OK then the sensor itself is suspect.

Deal with the front sensor error first and the rear sensor related error will likely fix itself.

...Lee

2012 · Post by **2012** » 26 Jan 2015, 13:58

Thanks! Front sensor like 30 bucks on ebay hopefully that cures this light. I love these cars coz parts are plentiful and cheap!

Post by **Ozark Lee** » 26 Jan 2015, 14:59

I would avoid any oxygen sensor that is not Bosch and even the Bosch Universals can cause problems.

...Lee

Post by **misha** » 26 Jan 2015, 15:03

2012 wrote:... love these cars coz parts are plentiful and cheap!

You got something wrong here.Oem parts are not cheap at all

Aftemarket and crappy parts are cheap and usually don't last on these cars...if you have a luck to work at all.

All electronic parts Must be oem.Mechanical parts can be aftermarket,but there is a short list of brands which can be used and last on these cars.