Hi!

i have read that on this model there is not a
really an appreciable difference in gas mileage, i know it is for
keeping the gases wihtin the manufacturer range... but usually it
improves the fuel mileage since without it (the o2 sensor) the system by
default would set to a rich mixture...

after installed the new
o2 sensor, the check engine light went off and the mileage increased by
0.6 or 1mpg (several method to measure)

but i wonder

please, check the image

 

i know the sensor should be installed like the no. 1 example
BUT mine (after relocated, because this vehicle had catalitic removed)
the
muffler guy installed like the no. 2, he told me that the o2 sensor
does not need to be in "full" contact with the gases, that only needs a
"little" doze of the gases in order to make its job....
not too
satisfied with this, i wanted to ask you if i should go back to the
muffler shop and make him to desolder the o2 sensor socket again and to
make him to solder at its correct level so the part of the o2 sensor
that must be exposed to the gases is fully exposed?

just like the no.1?

Edited May 20, 20169 yr by Kharl

If you're talking about the rear o2 sensor, without a cat the second method will generally work better and keep the engine light off. The rear o2 sensor doesn't do a whole lot for engine tuning, it's mostly emissions.

 

If you're talking about the front sensor, it needs to be fully is the exhaust stream or you'll have the wrong mixture.

If you're talking about the rear o2 sensor, without a cat the second method will generally work better and keep the engine light off. The rear o2 sensor doesn't do a whole lot for engine tuning, it's mostly emissions.

 

If you're talking about the front sensor, it needs to be fully is the exhaust stream or you'll have the wrong mixture.

 

thank you for answer

 

this vehicle only has one o2 sensor

I assumed you have an EJ subaru which have two sensors in the US. What exactly is your car?

I assumed you have an EJ subaru which have two sensors in the US. What exactly is your car?

Subaru Legacy 93 L

Station Wagon FWD

USDM