cleaning O2 sesnors

[johnouellette]

I installed a gpop k03/k04 turbo a couple weeks ago and blew the hot side seals and bearing after about 60 miles. I lost about 4qts of oil into my brand new borla exhaust . I have a test pipe so I won't have to worry about a clogged cat, but I don't know what to do with the O2 sensors. Can they be cleaned off with carb cleaner or something? I don't want to spend money on buying new ones if it's not needed.

[diagnosticator]

Don't clean the sensors with anything. The exhaust heat will burn off any oil residue.

[johnouellette]

hopefully they still function properly.

[diagnosticator]

The pre cat sensor is the only one involved with fuel mixture control, the post cat sensor is only involved with evaluating the cat functional efficiency, in your case that is irrelevant. The O2 sensor probably won't provide accurate info to the ECU until it has a chance to clean up from driving for awhile. You can force the ECU to run open loop by disconnection the sensor, then drive the car like you stole it for a few miles and shut down and reconnect the sensor, to see if it going to be OK. If not, then you can consider cleaning with something, but it's not a good idea to clean it first because of the chance of wrecking an otherwise good sensor that only needs the oil burned off.

[Affinitive]

O2 sensors and even Catalytic Converters (irrelevant to you) are surprisingly resiliant to massive oil exposure. Seen a number of 2.7T's and 1.8T's with blown turbos and O2's would hold up for quite a long time after repairs. Same with P-Cars and BMTroubleyou's when the Oil Seperators fail leaving oil dripping out of the tailpipe.
Mr. Diag is just about spot on. Just drive the hell out of it after repairs for about 50 miles or so and clear whatever faults set. You'll probably be fine afterwards, if not, I doubt cleaning will prove successful. Something else to consider, O2's are basicly 100K throw away parts anyways (give or take a little), so if you're close to that mileage range, you may wana consider just replacing anyways.

C

[pondside36]

Some good info right here.. I didn't know that the O2 sensor had a certain life, ie around 100K.. I'm at 98k, guess I should set aside a few bucks...

[tj19855]

maybe you guys can help me, I got my new o2 sensors connected to the ECU but not in the exhaust yet, my cats are clogged and need to be replaced or test pipe/downpipe. Im getting this code

16514 - Oxygen (Lambda) Sensor B1 S1: Malfunction in Circuit
P0130 - 008 - Implausible Signal
16534 - Oxygen (Lambda) Sensor B2 S1: Malfunction in Circuit
P0150 - 008 - Implausible Signal
Readiness: 0110 1101

If I get a down pipe/test pipe with o2 foolers would i get any codes?

[Affinitive]

What do you mean O2 Foolers???????????
You mean like adaptors which will pull the rear O2's out of the exhaust flow a little???? or I guess you could say limiting the exhaust gas exposure to the rear O2's????

C

[tj19855]

o2 foolers = spacers

[Affinitive]

^^^One nice thing about late model Audi's and VW's is that the O2 and cat Efficiency monitoring/self testing strategies is so fine tuned that it basicly means that if the car says the O2's or cats are failing, then they are failing. Granted, a few models have updated software due to cat monitoring being too sensitive. I generally see O2's failing in the 80 - 100K range. Sometimes as early as 60K. But very seldomly see cars with original O2's far beyond 100K. It's basicly an engineered life span. Interestingly enough, BOSCH actually recomends replacement no later than 100K, so obviously they engineer the things to last about 100K.

C

[Affinitive]

^^
Ahh, got it. It could very well work. Though I wouldn't hold my breath. I generally always see aftermarket exhaust causing problems setting faults. Though I think it boils down to the fact that most aftermarket exhaust is not engineered properly and people not loading custom software to accomodate the custom hardware.
besides that, Cat don't actually restrict performance. At least not until you get into the super high performance range.

C

[tj19855]

Yah that is why I'm worried if I get a down pipe, maybe i should stick with a new stock cat, so I won't be having any issues.

[diagnosticator]

Yah that is why I'm worried if I get a down pipe, maybe i should stick with a new stock cat, so I won't be having any issues.

I agree. The cause of the two DTCs is that the sensors are in open air with the ecu/eingine runing, and the O2 measured is not what is normal for exhaust gas, so the sensor signal is inplausable.

[dirtybrd]

Yes, o2 sensors are "wear" items like spark plugs, and do slowly go bad over time.