Couple of Codes

[KarmannMarco]

Hi guys , my CEL came on the other day. I went to autozone to pull the coded and pulled a P0161 ( 02 sensor bank 2 ) and P0500 ( Vehicle speed sensor ).
Could these two be related to each other ? In the 3 months I've owned the truck it's never had a CEL and I pulled the codes immediately after it came on so Im guessing they are either related to one another or one of the two does not cause the CEL to come on.
The truck is a 97 Montero LS with 134K miles.
Only other things wrong with it are that it burns about a qt. of oil a month (common issue) and it smokes a little (not much at all but I figured it's because of the oil burning....maybe 02 sensor related now?)
There are no drivability issues at all. Truck runs smooth and quietly.
Any ideas what is the best way to diagnose this CEL rather then throw parts at it ?

Thanks in advance.

Marco

 

[89 monty]

I dont think they are related....VSS (PO500) is related to the speed sensors at the knuckles... The smoking is probably valve seals, and the 02 could have been toasted by the oil contamination.
Id replace the valve seals, and 02...then look into a possible bad VSS wire or actual sensor...

 

[KarmannMarco]

Thanks for the suggestions! Ill go ahead and order the 02 sensor..... if i don't replace the valve seals will it hurt anything ? At last in the short term.

I'll check the VSS wire. If the a VSS on each knuckle?

Thanks

 

[off-roader]

From what I recall, oil in the exhaust will cause problems with the O2 sensors, cat convertor (clogs it), and smog laws. FWIW, I've had valve guide seal issues with my 96SR since I've owned it but it's continued to run fine w/out any OBDII issues. I do intend to fix the problem sooner than later (once I get my other car back from doing maintenance on it).

HTH.

 

[KarmannMarco]

Would the 02 sensor in bank 2 , location 2 be considered downstream...... if its after the cat...? Different companies use different terminology and I want to replace the right sensor once..... form what I remember bank two is the opposite side of where piston #1 fires and location two is the sensor after the cat correct? Do our trucks really have 4 02 sensors?

 

[off-roader]

Would the 02 sensor in bank 2 , location 2 be considered downstream...... if its after the cat...? Different companies use different terminology and I want to replace the right sensor once..... form what I remember bank two is the opposite side of where piston #1 fires and location two is the sensor after the cat correct? Do our trucks really have 4 02 sensors?

Downstream means after the exhaust which the O2 sensors are, so yeas all of them are downstream. Not sure which banks are which. Not sure how many so download and check the FSM (fact. svc. manual) or ASA program (actual Mitsu parts lookup program... Windows only) to see how many we have.

 

[kuroi]

After cat is down stream, pre cat is up stream. pre cat is used to regulate air fuel ratio in closed loop down stream is used to monitor cat efficiency