[Ramm440]

I had this trip the SES light so took I it to an indy and they gave me two options,

1)Replace bank 2 up and downstream o2 sensors for $875.00

2)Replace bank 1 and and 2 up and downstream sensors for $1600.00

I have found all 4 Bosch replacements for approximately $450.00 @ fcp euro.

I am going to diy it…..My Question is, Is it usually the upstream o2 that fails and trips p2098 code or can it be the downstream causing it to fail? Is it best to change all 4 since the car has 113,000 miles?
Thanks

[marvinstockman]

P2098 is an engine oil over temperature:

https://www.dtcdecode.com/BMW/P0298

[Boston4]

Originally Posted by marvinstockman

P2098 is an engine oil over temperature:

https://www.dtcdecode.com/BMW/P0298

He said P2098, not P0298.

https://www.dtcdecode.com/BMW/P2098

I think correct diagnosis would be to look at live data from the O2 sensors to identify which ones are defective and then visually inspect for damage to wiring (e.g. melting) and repair or replace as necessary.

Personally I wouldn't replace O2 sensors proactively.

Also: P2098 is a generic code that you'd get from a non-BMW specific code reader. I'd want to see the actual BMW codes in the DME since they're much more detailed and will help your issue triage. You can do this with an app and dongle (Bimmerlink or Carly) - surprising that the indy pulled the generic ones.

[marvinstockman]

Must be age related dyslexia on my part.

[Ramm440]

I have used this indy shop for a number of years and they are not very forth coming on sharing much details from their diagnosis so I am going by the recommendation of their mechanic. I really do not like the service adviser because one time I asked to see my failed parts and it was so inconvenient for him to locate them wtf rt? This is all they would provide. They have not misdiagnosed anything in the past but I still don’t want to go back.

https://botimage.blob.core.windows.net/images/8EDE7446-E5F0-45A1-9C51-D1EE646BA5C8.png

https://botimage.blob.core.windows.net/images/D3C96E4B-2CBD-4F7D-9FAF-4EA4BB9F9B30.png

TECHNICIAN NOTE
Fault stored for the bank 2 post catalytic converter oxygen sensor. As per the fault data description it is recommended to replace both bank 2 sensors, and it is also recommended to replace all oxygen sensors every 120,000 miles (vehicle currently has 113,000).

RECOMMENDATION
Replace all four oxygen sensors.-$1580___If customer just wants to replace both bank 2 oxygen sensors.-$875

[Ramm440]

Sorry that the p2098 was from my cheap reader not the indy.

[Ramm440]

http://http://2un.me/ttzlpygv

[Ramm440]

Originally Posted by Ramm440

http://http://2un.me/ttzlpygv

This is all the shop showed me

[Ramm440]

Looks like the code the shop got was 002C32….
Anyone confirm if this is o2 related
Thanks

[mainbearing]

That looks like Bank 2 post catalyst fuel trim too lean.

You need to check for exhaust cracks that allow air to enter as well.

I think the upstream sensors have different wire colors but the same connector. In that case you might want to temporarily swap the two upstream sensors and see if the code changes to Bank 1.

If it does, then change the original bank 2 upstream (or both upstream sensors since you are DIYing).

Be careful of counterfeit sensors on flea bay. You can check Rock Auto or RM European for Bosch.

[Ramm440]

Thanks, great idea to swap at the plugin connector

[Ramm440]

Idk why the shop wants this much when they quoted me using Bosch sensors. The BMW ones are really high in$$$ and made by Bosch?? Rt?

[mainbearing]

Just to clarify, you do not mean just the connectors, right? I meant to swap both upstream sensors, and just let the wires route directly up to the valve cover for simplicity.

However, if you do that is an interesting point, what if just swapping the connectors? I do not know.

Also check the prices on Rock Auto. Although FCP will have lifetime replacement warranty, so that can be an advantage.

[mainbearing]

Yes, Bosch is the OEM maker of the sensors. If you look on Rock Auto, Denso's pictures for the downstream sensors look like Bosch (the actual contents may change). And you save a few more bucks going with Denso if you ever decide to change the downstream sensors. For upstream sensor definitely go with Bosch to avoid problems.

If there are no exhaust pipe leaks or other problems, I wonder if the problems are with the upstream sensor(s).

[Ramm440]

Do you know if I need to clear the code with my cheap reader which I did once or if replace the faulty sensor it will clear after a couple of drive cycles?

[mainbearing]

You should be able to clear the code with any generic reader.

And if a new sensor solves the problem, the code should disappear after the monitor program runs.

What is your plan now?

[Ramm440]

Just checked Rock Auto decent price difference…for Bosch
Thanks!!

[Ramm440]

I will start with bank 2 upstream… one at a time and test it then go for bank 2 downstream if that doesn’t solve it. I will repost my results and greatly appreciate your input!

[mainbearing]

Sounds good. Hopefully it is just a sensor and not something cracked letting unmetered air in.

[F31B48]

What he said ^^^^^^^^^^
Have you checked for air leaks? That's the most likely cause.

[gbalthrop]

If you paid that shop for their "Diagnosis" and Grossly Over-priced Estimate ($1600 to replace sensors costing ~ $400 Retail) you should DEMAND to know what diagnostics they performed, ALL Fault Codes and Freeze Frame Data read, and WHAT they recommend to test or replace. As I read the BMW Fault Code Lookup Fault Information Sheet for P2098 (Hex-code equivalent = 2C32), that code automatically triggers an "Active Test" and there should be an additional Fault code saved in DME Fault Memory. Here are ISTA Definition and Fault Info Sheet LINK:
P2098 | 2C32 | Oxygen Sensor Before Catalytic Converter, Bank 2, Trim Control
Also: DME: Lambda Control 2
https://bmwfault.codes/XMLDiagView?d...IANgAyADAANAA=

If you needed one or more Replacement O2 Sensors, Autohaus is near you and is a very good "Old-School" reliable, reasonably-priced, parts house:
https://www.autohausaz.com/catalog/k...xygen%20sensor

Do you have a Scan Tool available that can display STFT (Short Term Fuel Trims)? If NOT sure, please provide the Make & Model of Scan Tool. Many basic Scan Tools can show you Live Data of the signal from each of the 4 O2 Sensors, so you do NOT have to guess what signal the DME is receiving from EACH.

I would suggest getting Fault Codes in DME (Engine Control Module) read at Advance Auto, Autozone, etc. if you are NOT experienced reading codes. As stated earlier, there SHOULD be ANOTHER fault code in addition to P2098/2C32.

Rather than throw parts, since there is NO improper operation (ONLY an SES light), I would suggest taking this opportunity to learn a bit about Diagnostics, and to make sure you don't just have a wiring issue or such, BEFORE you order any parts.

If you have a Windows OS Laptop, I would suggest paying $45 for a BimmerGeeks K+DCAN Cable to connect Laptop to Vehicle OBD II Socket, getting FREE Download of BMW Standard Tools, which includes INPA, BMW Factory-Level Diagnostic Software, and "DIAGNOSING IT YOURSELF" with the help of Forum Members.
George

[Ramm440]

Thank you George!
Since the wife only likes apple I don’t have a windows laptop. Is there a reasonably priced scan tool you recommend? I will drive the car to a-zone and request the detailed information on the fault codes and take pics for now. I am really disgusted how this shop will take advantage of customers. As I mentioned before in my earlier post it was a big inconvenience to gather my old parts from a prior repair. I appreciate all the time you spent in responding and gathering the links!