rhonster

What could cause the right bank oxygen sensor (upstream inside) to wear out much more frequently than either the front or downstream sensor?

Quickywd01

iTrader: (16)

Uneven bank AFR.

rhonster

Is there an Air-Fuel-Ratio sensor for the 97 Max? where is it?

asand1

iTrader: (1)

AFR=air fuel ratio. Your right bank could be lean causing excessive heat, but you would have a lean code.
More likely that you are leaking oil from your valve cover onto the sensor and killing it.

rhonster

I am not getting any codes other than 0503 for the o2 sensor. It comes out dry with no apparent oil residue on it. Is it possible the front bank o2 sensor has been neutralized to be unfunctional, in the ecu, somehow which presumably would cause an unbalance?

asand1

iTrader: (1)

Is there oil on the OUTSIDE body of the sensor?

asand1

iTrader: (1)

No.

rhonster

No, the sensor comes out dry and looking normal, i.e. no excessive heat or residue indications.

bchepurny

I have the same exact problem! I replaced that right bank o2 sensor and now several months later, the check engine light is back on with the 0503 code. I know how to reset the check engine light but after driving for about a minute, it comes back on with the same code. Im going to my buddy's shop to check it out. Maybe I'll replace it and see if it's better because I put a really cheap 02 sensor in there.

GGENIUS

iTrader: (1)

check all your fuses. there was just a thread recently where dude took his car to a nissan dealer for O2 codes and they replaced them only to find out it was a couple blown fuses throwing the codes. AFTER paying to replace the O2 sensors first of course.

rhonster

I re-replaced the o2 with a plug and play I got off eBay for about $25, made in Singapore. Seems to be ok. Maybe the right bank (firewall side) sensors go more frequently being on the lee side or the side out of the wind, so to speak.

Let us know what you find out.