Toyota Vitz 2nd Gen - Replacing O2 sensor started giving black smoke

[pwuser160544620267]

Hello Everyone,

I was getting P0137 code on my 2007 2nd Gen Vitz. I went to the market and purchased a 2nd hand oxygen sensor.

Disconnected the battery terminals.

Removed the previous sensor from the catalytic converter.

Cleaned the new sensor using contact cleaner.

Cleaned the connector with contact cleaner as well.

Installed it and put the battery terminals back on.

Started the engine and the check emgine light was gone.

Drove the car for 10 kms and noticed that the car started rough idling on signals.

After that, the car started givings jerks sometimes.

In the night, I thought that the replaced O2 sensor is not right although it matches the code with the previous sensor.

Removed the sensor and it had black deposit on it.

Put the old sensor back and revved the engine and black smoke was coming from the silencer.

After revving it for sometime, the black smoke stopped.

I do not understand what went wrong with the replaced sensor.

Also, before replacing the sensor, my car didnt have any rough idle, no jerks and no black smoke.

Please guide me what could have happened. Thank you Pakwheelers

[horticulturalist]

Most of the scrap O2 sensors are bad... But btw why on earth did u change the sensor if it was fine????

[pwuser160544620267]

As I mentioned that the O2 sensor needs replacement. I am still running the car with the previous sensor and I have the check engine light On.

But my car has no rough idle, no black smoke, no jerks. Even the fuel mileage is pretty as usual.

[Xulfiqar]

P0137 means sensor is reading lean, did you actually check if the sensor was bad or you had something else causing this?

[chinyoti]

You have a bad EGR

[pwuser160544620267]

Well I have to depend on the diagnostic tests which the electricians run using the software. They showed me this code and told me that your Bank 1 O2 sensor needs replacement. I have another vitz same model and I replaced the sensor from that and drive for 2 weeks. My check engine was gone and the other car started having it.

If you have any other suggestion for me to check then I would be happy to follow that. I am located in Lahore by the way.

[pwuser160544620267]

I had it cleaned like a month ago so I doubt that it will be bad.

[Xulfiqar]

You cleaned an egr and expected it to fix a low voltage on primary o2?

[Xulfiqar]

There are lots of tests that are done to confirm why the fault is occuring and whats causing it.

Diagnosing something is not just reading a scan tool.

[chinyoti]

Also,

Black smoke, Weak engine is very common for these 1KR disposable engines.

One more thing. The vitz in question can have wiring problems which can lead to different codes. You fix one and another one arises.

You will need to visit a honest reliable shop. Else you will keep changing sensors and keep paid for scan tool diagnostic services.

[pwuser160544620267]

Thank you for your input. Cleaning EGR, Catalytic Converter, Injectors is my common routine after 15k kms. So I had it done regardless of any issues.

I had the engine rebuilt based on the Raja Atta's videos. I am totally satisfied with the engine overhaul but I will probably have to visit Raja Atta in Pindi to get all of this issue sorted.

Just to add, my car is working fine with the old sensor and the check engine comes and goes. Concerned about it yes but I havent had a chance to find a reliable person to run proper diagnostics.

Once again thank you for feedback

[pwuser160544620267]

This issue came up only with the new sensor I put in which was a second hand part. I cleaned it with Contact Cleaner which I have been told by Raja Atta that it has damaged the new sensor which I put in.

With the old sensor giving check engine light sporadically does not give me this issue. I messed up the changed sensor by cleaning it with a contact cleaner.

Will find time to visit Pindi and get this sorted out.

Thank you for your feedback

[chinyoti]

simply put, You can tell your mechanic to clean the old oxygen sensor with petrol and try installing it again.

Also try to look for a brand new oxygen sensor they arent very costly if you go and look from a parts shop.

Even if you get a Chinese brand new part that would be better then buying from the scrap market.

Buying disposable parts from scrap is never recomended, Often times they might be selling you locally used stuff claiming it to be KABULI (Japanese Used).

Mostly Corollas scrap imported in to Pakistan is from Singapore and Thailand, Even parts sellers suggest you not to buy thoose engines.

buying body parts from scrap is probably ok.

[Xulfiqar]

These procedures are self inventions of Pakistani mechanics only, and are not required at all.

The code you had shows up with an air leak in the exhaust or even intake, it needs to be verified first before changing.

[pwuser160544620267]

Thank you for your guidance. I am currently looking yo get settled with finding a new mechanic as my previous mechanic has closed his workshop and working. Again, I am in Lahore so if you know anyone reliable then please share details. I will make sure that I won't bug him

[pwuser160544620267]

I have tried finding a new one but I was unable to find the matching part number so had to opt for the scrap parts. I dont want to put back the sensor which went black. Thanks for your help and guidance.

[pwuser160544620267]

Issue is resolved. Basically the diagnostics was incorrect and after getting the proper diagnostics, it turned out that the Bank 2 Oxygen sensor was messed up. Replacing it has resolved the check engine light issue. Costed 4000.

[Xulfiqar]

Bank2?

My man you only have one bank of cylinders. Im going to assume you mean “bank1 sensor 2” also called “downstream sensor”

[pwuser160544620267]

Forgive my typo. Yes that is what I meant