oxygen sensor placement

**o_man_ra23** · 01-09-2009, 02:47 PM

Gday all,

I would like to know what the best placement for an oxygen sensor in a turbocharged application is. I have some conflicting information/observations which aren't helping, and would like some advice from those who know.

The advice I got is that the sensor should be as vertical as possible. In my application, this means the sensor needs to be mounted about an inch behind the outlet of the turbo in the dump pipe.

Observations are that the sensor is normally mounted about a foot or more down the dump pipe and often on its side. I am guessing the heat coming out of the turbo would likely do damage to the sensor fairly quickly, so a bit of room is given to not only cool the gasses a bit but also prevent turbulence just after the turbine wheel. In my case I would not be able to mount the sensor vertically if I do this. Will this cause an issue, or is horizontal fine for an oxygen sensor??

In my application, a wide band sensor will be used to start with, then changed out for a narrow band in the long term.

Helpful advice is appreciated.

**jeffro ra28** · 01-09-2009, 04:01 PM

Sensor should be above horizontal
The issue of turbo is too much heat, not turbulence. If it is heated sensor, you can put it a lot further back.
Wide band are more sensitive to heat.
The issue with angle, is if it is lower than horizontal, condensation can run into it, it does not need to be vertical, just up enough so water cant pool inside it

**o_man_ra23** · 01-09-2009, 04:04 PM

Thanks mate.

**The Witzl** · 01-09-2009, 04:29 PM

i put mine almost under the passenger footwell, mounted on about a 15* angle to horizontal.
Being a heated sensor, it worked perfectly.

**celicapain** · 02-09-2009, 02:56 PM

*as a note
I mounted mine slightly under horizontal

(READ INSTRUCTIONS BEFORE WELDING PPLS) which can apparantly give the condensation issue, but i havnt had a drama in the 18 months it;s been on the car, including getting saturated when i did a HG, so dont think its super critical. im running mine about 50 cm back from the turbine outlet.

**The Witzl** · 02-09-2009, 04:32 PM

it can particularly be a problem for wideband sensors AFAIK.

**wilbo666** · 02-09-2009, 06:56 PM

Techedge also have some advice, as do other WBO2 makere, might help as a guide

http://wbo2.com/lsu/position.htm

Cheers
Wilbo

**thechuckster** · 02-09-2009, 07:38 PM

mine was too close to the turbo (about 3 inches away) - a foot or more away from the turbo would be good. They have internal heaters so allowing the gas to cool really isn't the issue but excessive heat will make them do funky things and probably kill them in the long run.

mounting angle is to stop moisture getting into the sensor when car is stationary and cold - so upon startup+warmup, the unit doesn't pop.