DIY OXYGEN SENSOR O2 REPLACEMNT

[J.Millionaire]

My check engine light is on, I have been informed by my mechanic that I need a rear o2 sensor, Bank 1 replaced. I know what sensor I need but I don't how to tell the location of Rear sensor Bank 1, any info in locating this would be helpful. Also has anybody replaced thier o2 sensor? It seems fairly easy after watching a youtube video. This will allow me to save $75-$100 having a mechanic do it. Please Help, Thanks!

[03rangiemark]

I tried to send a reply earlier, but was timed-out while typing the reply. That discouraged me and I went on to do something else.
Basically, check w/ Autozone or Advance Auto parts to use one of their loaner tools - the socket to remove/install the O2 sensor. It's a socket with a cutout to accomodate the O2 sensors cable harness. O2 sensors are a common size.
When you install the new one, use antiseize or teflon tape on the threads to make it easier to remove next time, hopefully well over 100,000 miles from now.
The bank-1 downstream (#2) O2 sensor is on the passenger side (of a left-hand drive vehicle), after the catalytic converter. Look for the sensor threaded into a bung with a small cable coming out.

[J.Millionaire]

Thanks that helpful, just came back from Autozone and got my codes pulled, it gave me Code P1170 Bank 1, Sensor 1. Is that the same location that u suggested?

[03rangiemark]

...Bank 1, Sensor 1. Is that the same location that u suggested?

No, the #1 sensor is the upstream sensor, located BEFORE the catalytic converter.

[motosport3]

"lambda sensor aging fault, downstream fuel trim bank1."

This is what I have. I read on another forum that bank 1 was actually the driver side (left hand drive vehicle). Can someone confirm?

Is bank 1 mentioned in the RAVE anywhere?

[motosport3]

Sorry, I'm not that savvy when it comes to all of this..

Rave says

Left bank is cylinders 5-8
Right Bank is cylinders 1-4

I'm assuming this is with me looking at the engine straight on from the front of the vehicle so that would mean Bank 1 is the passenger side.

To keep it simple is Bank 1 the driver side on a left hand drive vehicle?

Thanks. I swapped the O2 sensor on the downstream on the driver side based on that fact, but the CEL came back on with P1170 fault code and I just want to clarify if I changed the wrong one.

[03rangiemark]

...Rave says
Left bank is cylinders 5-8
Right Bank is cylinders 1-4.

That's correct.

...I'm assuming this is with me looking at the engine straight on from the front of the vehicle so that would mean Bank 1 is the passenger side.
To keep it simple is Bank 1 the driver side on a left hand drive vehicle?

If you look in the RAVE manual, 12.29.02 & 12.29.03 cover replacing the left hand and right hand head gaskets, respectively. Looking at the illustrations in those sections, the LH bank is on the passenger side, on a left-hand drive which suggests that the reference of left and right is from the rear of the engine. This is the general convention - as you face the engine compartment from the front, the left side of the engine is on your right, and so forth.

...Thanks. I swapped the O2 sensor on the downstream on the driver side based on that fact, but the CEL came back on with P1170 fault code and I just want to clarify if I changed the wrong one.

O2 sensors are often replaced when it's not where the problem originates. It's a classic case of "shooting the messenger". The O2 will report a failure of something further upstream that causes the exhaust mixture to be unacceptable. The O2 sensors just measure and report.
Not that they don't fail, and that it's not your case; it may well be, assuming you've checked details for the P1170 fault code. It could also be caused by the sensor being disconnected or various other things. You could alsways swap sides and see if the problem follows the suspect sensor. And since you changed the bank-2 O2 sensor, might as well.

[RRToadHall]

...the LH bank is on the passenger side, on a left-hand drive which suggests that the reference of left and right is from the rear of the engine...

If referenced from the rear of the engine on a left hand drive rig the passenger side would be right, not left.

[03rangiemark]

If referenced from the rear of the engine on a left hand drive rig the passenger side would be right, not left.

Oops, yeah. It's been a long day & I got sloppy on that. I meant that the passenger side is the RH (bank-1).
Easiest way to remember is that when you are sitting in the vehicle, which is right and which is left? Sides of the vehicle (including the engine) are referenced from the drivers perspective.

Not too helpful in a front-wheel drive with a transverse mounted engine though.
Thanks for the good catch!. I appreciate it.

[RRToadHall]

Transverse engines are always referenced from the front to back. Left bank front, right bank rear.

[motosport3]

Thanks for the responses. Looks like I swapped the incorrect sensor out then since my fault was for Bank 1 Downstream.

In short:

Bank 1 is the Passenger side on LHD cars.
Bank 2 is the Drivers side on LHD cars.