Glen McCartney

I am going to be installing and working with the Innovate LM-2 sometime next week. I read somewhere, but now I cant find it, that you shouldn't leave the WBO2 sensor in the exhaust stream without it being powered up.

After doing some data logging, I wasn't planning on leaving the LM-2 connected but was going to leave the WBO2 in the X-pipe.

Anyone know?

Thanks.
Glen

Rob Edwards

Bad idea. Either leave it powered when the car is running or remove it.

Are you Sharktuning with the LM-2 or just datalogging? If the former I'd be interested in seeing how you interfaced the LM-2 with the ST.

Glen McCartney

Rob,
Just using it to data log. I installed the Porken S300S racing chip set and want to do some logging to see if there is more to be had. Ken has tuned the chips in his car, 5 speed, mine is an auto.

Thanks
Glen

dcrasta

I would take it out and put a plug in, or hook it up to a WB gauge and have real a/f ratios while driving..

blown 87

I agree, Innovate says do not do it.

Opelotus

In what way is the O2 sensor damaged if it is unplugged?

neilh

An O2 sensor has a heater element in it, if the heater is not hot, the hot exhaust gases will quickly destroy it.

Opelotus

In that case, how does it not get destroyed during normal operation?

neilh

'cause its internal heater is on all the time!

Opelotus

Don't mean to be a pain, but I don't see how that makes a difference

ptuomov

Here's what I think but do not know.

The risk with leaving it in unpowered is that it becomes clogged with carbon (which would normally burn off). Not advised, but I don't think this is a guaranteed destruction.

What really kills the sensor is water. Long term exposure is one way, having the sensor pointing downwards and the water inside the pipe condensing in it is a no-no. Even quicker way to kill it, though, is to first heat the sensor before starting and then have the engine cough up some water from the exhaust on it. I think it'll pop.

If none of this succeeds in killing the sensor, you can always try prolonged exposure to leaded race gas exhaust...

Opelotus

Is the O2 heater circuit on whenever the key is in the run position, or only when the engine is running?

123quattro

Actually having the sensor in the bottom of a pipe pointed up is worse for moisture.

The heater on a UEGO or narrow-band sensor is to get the sensor warm enough to operate. This allows the engine to go into closed loop operation faster as you don't have to wait ~30 seconds for the exhaust energy to get the sensor going.

You can drive thousands of miles with an unpowered sensor in the exhaust. However, if you aren't reading it, pull it and install a bung. There is no reason to put miles on a sensor that costs $100 for no reason.

PorKen

The factory O2 sensor heater is powered by the fuel pump relay (injectors too).

Ed Scherer

FWIW, TechEdge says (and this is probably the same for all WBO2 sensors):

• Pump Cell sensors (like the LSU) should not be exposed to an exhaust stream and left unheated. The internal diffusion chamber will readily clog with carbon deposits that would be "burnt off" in normal operation.
• If your wideband unit is disconnected for any length of time (> 10 minutes), you should also remove the sensor and replace the nut in the bung.