Into (long) and Questions about O2 sensor failures - P0030

B6/7 S4/RS4
#2

Welcome to AR, Jed. We are definitely a sensible bunch! Car looks fantastic. I’m sure the RS4 guys will chime in regarding the O2 issue.

#3

Welcome to AR Justin! Glad to have you here!

#4

that pic looks so rich. Good camera?

http://farm8.staticflickr.com/7393/11498248435_8fafa4970a_b_d.jpg

#5

ps as for the o2 sensor it sounds like the code is definitely pointing to you needing B1S1 replaced, but keep looking in case there’s anything you can do to avoid the $200 sensor cost etc.

When my exhaust was installed, my B1S1 died as well funny enough. I had it replaced, and no problems. I looked at it like this…these things don’t last forever and are pretty important, so I don’t mind replacing it at 50,000 miles or whatever. I plan to replace the B2S1 as well as all my coilpacks etc. in the next wee while as I just like keeping things fresh. 50,000 miles is a fair amount of life to get out of a sensor so don’t feel bad!

#6

My buddy who is big into photography went out with me and captured some great pics. I only uploaded 2. He wasn’t proud of them, but I thought they are great compared to my iPhone shots. We will be going out again in spring for a more formal shoot. No idea on his equipment as I don’t speak that jargon.

I’m with you on doing a look over on all connections and such, but I’m going to stomach the small cost on a “wear and tear” part. I will feel so much better knowing the car can dial it self in properly with that sensor working. Definitely will take a cautious approach to down pipe installation in the future. I think I’ll just replace the faulty one this time and leave the others alone. Interesting coincidence on the sensor. I’ve been thinking about my coil packs as last winter I had a misfire. Resolved itself and was a one time mishap on a cold start (I think it was like 5 degrees out). Car has gone some time in good health, but I always like being pro-active when it comes to maintenance.

Thanks for all the welcomes!!

#7

Does anyone have any actual proof that the new flow kills the sensors? Aside from it happening a lot on Audi’s, I can’t find cases of the same thing happening on any other platform.

Should increasing the boost and going catless at the same time kill the sensors on my Cobra? It didn’t, and it didn’t happen on any other Cobras. No cases of it happening on Subarus, Evos, Corvettes, etc.

#8

I don’t know if this is something that I would be able to put my finger on… I can say it has been consistant when you look across all the platforms if the 02s are of a higher mileage adding more power tends to blow them. On the 2.7T and 1.8T it was almost a given if you got a tune on your ko3 car you had better get 02s

exhaust work seems like an easy time to damage the wires or the filiment in the 02s. This is something we see often

#9

Not many domestic vehicles have widebands, right? I wonder if the sensitivity of the VAG sensors has anything to do with it, kinda like Chris mentions.

#10

well it happens. Can you unkill them for us when they die, since you own a Mustang?

#11

I also had both my B1/2 S1 sensors fail after I finished up my exhaust install, at 87k I just bought new ones, got pretty good mileage from the stock ones.

Any thoughts on maybe the sensors getting roughed up/damaged during the exhaust removal/installation? Just notice Chris also mentioned this.

#12

Went to headers about 5000 miles ago. Had a brief encounter with a “Too Lean” problem. That got fixed with an IM retorque. Nothing since.

#13

definitely a concern

#14

I’m sure the shop that installed would claim no intentional harm done and the sensor was on its way out. Seems as if o2 sensors have a finite life. I was surprised that flow could be the killer. If it’s normal for these cars than cheaper to just replace and be glad they lasted this long. Does seem that they’d last longer on a stock vehicle.

#15

They get roughed up during install? This only happens on Audi’s apparently. It also is not tune dependent since lots of people report failures that did not get a tune at the same time. I just don’t understand why the Audi sensors fail. They are Bosch, same sensor pretty much everyone uses.

How much more air is flowing on a V8 S4 going from stock to full catless?

#16

I’m not sure it’s just flow. There are loads of factors.

I also think this happens on every car. O2 sensors are always dying. Type in any random dead o2 code and you will get links from dozens of platforms.

Not sure why you think they don’t die on mustangs either…or why you think the mustang use the same ones.

http://www.svtperformance.com/forums/new-edge-cobras-51/947881-wideband-o2-sensor-fuel-pump-questions.html

#17

Yeah I know O2 sensors die a lot on different cars. I just replaced one on my sisters Jeep.

But it is well known that exhaust modification almost always leads to sensor failure on Audi’s. I’m just trying to understand why. The rate of failure on Audi’s that have a modified exhaust is crazy.

There’s only a handful of O2 sensor manufactures in the world. Bosch makes the ones that come on an Audi and the ones that come on a Ford. So failure rates should be similar. You can use a universal sensor for the secondary sensors on an Audi, so those are clearly nothing special.

Since when is “it just happens” and “there are loads of factors” satisfactory answers on Audi Revolution? That’s Audizine level

#18

yes, there are loads of factors

  1. they just die. Shit happens.

  2. they get physically fucked up on removal or reinstall

  3. this happens on all platforms, not just Audi. You want to believe it’s only Audi, but it’s not. See the Cobra guy whose very basic sensors were all near dead? He just ditched them before they died. I have seen on the US platforms the guys will monitor their o2 sensors when doing a revitalization or a build, and if they’re not firing properly, they will replace them. We Audi guys just run them into the ground.

  4. the ECU relies on Audi sensors far more than the ECU on many domestic platforms. They work the little bastards to death. Wideband is a whole different animal. Perhaps it IS different on the Audis.

fact is, shit happens. It’s a $100-200 pain in the ass. You just have to eat shit on these ones! It’s like tires and spark plugs and oil filters. You need new ones after a while, so there you have it.

Here’s a selection of SVT performance threads. Maybe ask them why their sensors are always dying?

Actively replacing before death
http://www.svtperformance.com/forums/exhaust-215/961667-ntk-45-o2-sensors-bosch-25-sensors.html

Guy put a catback on and is throwing codes
http://www.svtperformance.com/forums/2011-2014-mustangs-354/990654-o2-sensor-code-thrown-bank-2-sensor-2-a.html

Faulty senor and coded out rears
http://www.svtperformance.com/forums/svt-shelby-gt500-150/948815-o2-sensor-question.html

Full exhaust and SC and loads of o2 codes/problems
http://www.svtperformance.com/forums/mach-1-156/887846-o2-sensor-help.html

Installed headers and killed a sensor
http://www.svtperformance.com/forums/2011-2014-mustangs-354/907410-bank-1-o2-sensor-failing.html

Sensors gone bad on his longtube car
http://www.svtperformance.com/forums/2011-2014-mustangs-354/960994-removing-oxygen-sensor-extensions-how.html

Supercharged and sensors are now dead
http://www.svtperformance.com/forums/engine-tuning-214/956451-front-o2s-not-switching-static-voltage.html

Exhaust installed, failing smog due to bad o2s now
http://www.svtperformance.com/forums/2011-2014-mustangs-354/961325-posting-heads-up-those-facing-smog-future.html

Tuned his car and now sensor is dead
http://www.svtperformance.com/forums/2011-2014-mustangs-354/979599-p2626-code-evening.html

#19
#20

Wanted to drop an update on this. Had the B1S1 O2 sensor checked for issues and of course, it looks to be in perfect condition. The sensor was not roughed up during install when I had the down pipes put in. No real answer to why it would have failed, but the heater circuit had definitely failed on the original O2 sensor. This being an important sensor I was comfortable just replacing it. New sensor I ordered from JHM, who ensured I got the correct part #, was put in and codes were cleared. Appeared to have resolved the issue, but just in case, emissions readiness test were done. Found out that cylinder 6 and 8 had been misfiring so out come the spark plugs to have a look. They were found to be the original factory ones, so had them replaced to see if it would help. Conduct some more testing and we decided it’d be best to replace the two coil packs on cylinder 6 and 8. Of course, cylinder 8 is an inconvenient coil to replace, but not a big deal. A test drive and readiness test were done again to make sure that all cylinders were firing with no issues and the O2 sensors were working properly. Everything passed and looked healthy. Still had my concerns knowing how the ecu will wait for a few cycles and extended drives before it throws a code. Cars been through a couple hundred miles and started multiple times and no codes! Engine sounds better, even though it could be a placebo, but I swear I used to hear something around 2000 rpm that sounded off that has completely gone away. Car seems to start better, run better, and improved fuel mileage by about 10%. That’s done with math at the fuel pump since I only get about 250miles before a fill up. With all new fluids/filters in the car and knowing that everything is running smoothly I am a very happy RS4 owner. The only thing I can imagine needs doing is a carbon clean (never performed 45k on the car) and the shop has recently purchased a blaster as they’ve had so many FSI (Q7, RS4, etc) coming in. I’ve seen some before and after shots and watched them working on a Q7 4.2 and feel comfortable having them do the work (I don’t have 6-12 hours to do it myself currently). Planning on enjoying the car till 50k and getting it done then.

What I’ve learned is that exhaust installs on these cars and failed O2 sensors happens and it’s good insurance to be ready to replace them. I’m personally a don’t fix it if it’s not broke kinda guy, so will just keep an eye on the others. I suspect that sensors that are on there way out and increased exhaust flow has the potential to ‘kill’ them. The filaments could also be sensitive to un-install, but I’m not blaming that event for failure. Definitely important to keep fresh plugs on these cars and it’s good insurance to replace coil packs. Prices aren’t horrible on either and the car runs well even when they’re old.

Thanks for the input guys. Can’t wait for warmer weather and to get a full detail done. I plan on getting some more shots up at blue ridge parkway for all to enjoy.

#21

Glad to hear everything is up to par now! Definitely get a carbon clean when you get a chance. It will be like getting a tune all over again!