2009 Clubman S.

February 2017 brought a small disaster. Burned 2 exhaust valves, cylinder 3.
No gradual decline, just CEL, miss and loss of power.

Head work, de-carbon, new plugs, etc., and CEL comes on shortly thereafter. Shop opines that they spilled coolant in the downstream connector, so blew dry and cleared codes.

CEL in March, code indicates upstream O2 sensor, which I replaced. Codes cleared, and OK for a few weeks. CEL isn't always on, so I have continued driving. Another CEL, into April and May, intermittent. Code is for downstream O2 sensor Replaced downstream in May, cleared code and got maybe a few weeks before CEL again. Remembered drippy coolant hose beneath expansion tank, thought maybe a short. CEL keeps coming back. Replaced downstream sensor again last week, and shop doing AC recharge scoped it for me, and said they saw code for MAF, which I replaced with OEM Bosch unit Saturday June 24. CEL came on again after 4-5 hours.

Any ideas about next step? Dealer? Local BMW specialist? Original shop where valve work done?

Thanks to all!

 

February 2017. 96000 miles. Car burned two exhaust valves in cyl. 3
Valve job, new valve cover, spark plugs, coil packs, walnut blast, etc...
March-April 2017 CEL light with code for upstream O2 sensor, replaced
April-May 2017 CEL for downstream O2 sensor, replaced
May-June 2017 Continuing CEL P0136, replaced downstream O2 sensor again
Tech @ Independent Garage fixed AC charge and read code for MAF, replaced
Yesterday OBD read P2270 and P0136, today just P0136

Any ideas? I would like to resolve this. Thanks

 

Sent you a PM.

It appears that as you are a member that did not post before the original post was not immediately released to the general membership. Nobody saw it and perhaps that is why you did not get the responses you thought you should have. The link from your posting in the Clubman section does appear to be working.

 

My only complaint was that I was not informed of the move, nor did the link work from my desktop.

 

Can only suggest you review the site guidelines and I as stated previously, the link appears to be working now.

Please let me know if there is anything else we can do.

 

I am the moderator covering Gen2, sorry to hear that you were having problems.

I saw that your thread was moderated (since it was your first post) and approved it. Then I moved it to the proper section (this one.) The moderators will do their best to move threads to the right place to keep the forum organized, it isn't always obvious where a thread should go. When we move threads, they are marked as "Moved" in the original location and then when you click on the thread it will re-direct you to the new location. The link seems to be working, so I can't tell if something went wrong.

In general I get to the forum every day, there are a lot of sections and a lot of threads to cover. We don't get automatic notice of new posts with Moderated status that need examination, so it may take 24-48 hours before someone sees your post and approves it. This is covered here: https://www.northamericanmotoring.co...ight-away.html That's what makes the 1st Gear forum a great place for a first post.

Anyway - back on topic. Your thread is now where it will get the widest audience and I'm sure one of the members will have some advice for you.

 

Your original thread was still marked as Moderated. Maybe the forum SW glitched, or maybe I screwed up - it happens. Since it had some additional detail I merged it with this one so everything is in one place.

Back on topic now....

 

you could have a bad Catalytic converter!

 

P0136 - O2 Sensor (Bank 1 Sensor 2)
P0136 - Oxygen sensor behind catalytic converter, electrical: Open circuit
P2270 - O2 Sensor Signal Stuck Lean (Bank 1 Sensor 2)

It is possible that it is the cat, but it sounds like an electrical problem to me.

If you don't already have this, get an OBD2 - Bluetooth converter and the Torque app for Android (or the equivalent converter and app for iPhone, do a search on the forum, lots of threads about this. For Android the converter will be about $20 and the app $5, less than a Friday night bar tab.) Use the app to monitor the O2 sensor outputs in real time, you'll be able to see right away if they are working and figure out if it is a sensor problem, electrical problem, or a bad cat. Unless you were burning a lot of oil, I doubt it is a bad cat.

 

Thanks All!

I use an Innova OBD2 reader. Will the bluetooth adapter and app give me more info?

I cleared the code then disconnected the battery for more than an hour this morning, then ran to a job site, round trip of maybe 3 miles.
No CEL as yet, but next time out, who knows. Generally it seems to blink back on after a few hours of driving.

It was only P0136 today. I also disconnected and inspected the downstream O2 plug. Would DEOxit or similar help?

The tech who did the valve work, etc. in Feb. thought that they might have spilled coolant on the downstream connector, and used heatgun/blowdrier to "solve" that, but the O2 codes, both upstream and downstream have been haunting me since.

 

I had similar problems with my Clubmans S with 130k miles. Chasing random O2 sensor codes. Finally after replacing both O2 Sensors 3 times i went for a CAT change. Problem disappeared. Not saying a CAT will definately fix your problem it it did for me.

Now 2100 miles later i am chasing an Evap Leak.

This car has been the most unreliable car i have owned now. Up to about 100k very little problems, thermostat and routine maint items like tires and oil changes. Since 100k many prroblems have arrisen, to many to list.

 

What are the signs of CAT failure? The car seems to be running fine. The car does go through a fair amount of oil. Mainly urban driving lately, not sure of actual miles, but requires a quart every couple weeks. I know that oil can gum up CATs.