White Smoke because o2 sensor missing?

S

SloaneSloane

Member
1 of my o2 sensors were broken during my install of a down pipe. The pipe is on without 1 of the sensors because it wont come in for 2 more days. Ever since the install of the down pipe my car started to smoke while i drive and at idle. The smoke is white so i went to the dealer and they said that the reason why its smoking is because missing 1 o2 sensor throws the computer off which is making it put more gas into the car then it needs which produces the white smoke. Is that true or is it the turbo seal problem that I read about.
 
Depends on which o2 sensor it is. If its the second one, I dont think it would do much other throw a CEL. Its there to moniter the cat and nothing else as far as I know. If its the first one, I would not drive the car till the sensor comes in. As far as the smoke, I would lean towards the turbo seals leaking. It may be hard to distinguish blue vs. white if its cold where you are.
 
SloaneSloane said:
its the back sensor and i live in hawaii so its warm and everyone says its white.
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Thats Coolent.. If it was the o2 and the car was running rich there would be black smoke/sut unburned fuel.. It could be a turbo seal at best.. or a Headgasket issue... What sort of boost are you running and does the car over heat?
 
car does not over heat and stock boost lvl only. The service manager says that the o2 sensor caused the problem and putting in the new one will solve it and stop the smoke. But i dont know what to believe.
 
Well it totally depends on the color of the smoke? An O2 sensor senses how much air is left unburned in the exhaust.. Obv if its not working it would either default or think the car is out of tune... Regardless your going to need a new o2 sensor.. Put it in and see if it goes away.. My guess is it wont if its white smoke... Depends on whos telling you its white and what it actually is

Coolent= White Smoke
Rich (to much fuel)= Black
Oil=Blue smoke
 
SloaneSloane said:
car does not over heat and stock boost lvl only. The service manager says that the o2 sensor caused the problem and putting in the new one will solve it and stop the smoke. But i dont know what to believe.
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The rear O2 sensor only tells the ECU if the Cat is working or not. The ECU only uses the 1st O2 reading (its a wideband) for fuel calculations.

And anyways, if it was dumping tons of fuel then the smoke would be black not white. Does the smoke have a bluish tint to it? I would bet that you are seeing burning oil from leaking turbo seals like a lot of other people who are freeing up their exhausts with a DP or race pipe. If you search for smoke + turbo seals you'll see a lot of post about it.

I would just wait until you get the O2 sensor in and then take it back to the dealer. 99% chance that the O2 sensor doesn't stop the smoke.

Good luck man and hopefully the dealer replaces your turbo without hassle.
 
If its really white, then its coolant. I would smell it. You would know if its oil. That 2nd sensor should just be looking for a voltage drop from the cat. It should not adjust the air fuel ratio at all. Unless something happened to your head gasket or something, I still would think its the turbo seals. Check your coolant level to make sure its not dropping.
 
Typically, white is coolant, blueish is oil, black is too rich.

You can further characterize the smoke as follows

-White coolant smoke dissipates pretty quickly and does not smell like burned oil
-Bluish oil smoke lasts much longer and definitely smells like burned oil
-Black smoke usually smells like gasoline

Hope this helps,
-enganear
 
i'm not a cert mechanic, but i'd say a bad o2 won't cause white smoke....my exp with bad o2 is they end up throwing more fuel, black smoke...white smoke as stated above is generally a coolant leak
 
You could always put the second cat back in and pretend its not doing it. Is yours an 07 or 08 out of curiosity? If its the turbo seals, you can drive it. You will need to have the dealer fix it eventually though.
 
it is an 07 and I got a cp-e downpipe so cant just put it back the 2nd cat. Well if it is the turbo seals atleast now i know so i can get it fixed.
 
If this happened right after the dp install then its gotta be the sensor. Funny part about it is i broke my first 02 sensor when i did my dp. $350 dollars later i have a new one. FACK!!!!!!!!!!!!!!!!!!!! Bull crap my car only has 4k miles on it and the sensor would not come out.
 
driver311 said:
If this happened right after the dp install then its gotta be the sensor. Funny part about it is i broke my first 02 sensor when i did my dp. $350 dollars later i have a new one. FACK!!!!!!!!!!!!!!!!!!!! Bull crap my car only has 4k miles on it and the sensor would not come out.
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The sensor you broke must have been the front WB O2 sensor. His was the rear sensor. The rear narrowband sensor is way cheaper (< $100). Plus it doesn't do any as far as fuel is concerned. Even if it did the smoke would be black (fuel related).
 
wisniaPl said:
I dont want to create new thread but Im curious did mazda fix issue with turbo seals in 08 models??
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No, some of the left over 2007 model turbos ended up in the 2008s...there are like 3-4 members with 2008s that have smoke... But its been mostly 2007s.

I don't know if its because 2008 are too new for people to start modding, but mine is not smoking as of now...(knock on wood)

See: http://www.mazdas247.com/forum/showthread.php?t=123691179
 
silverspd3 said:
If its really white, then its coolant. I would smell it. You would know if its oil. That 2nd sensor should just be looking for a voltage drop from the cat. It should not adjust the air fuel ratio at all. Unless something happened to your head gasket or something, I still would think its the turbo seals. Check your coolant level to make sure its not dropping.
Click to expand...

Yep, take a deep breath and suck in that wonderful exhaust. And close your garage door while your at it! :P j/p
 
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