Is there 1 or 2 O2 sensor on the 4cyl Mx3?

Prexus2005 · Post by **Prexus2005** » October 18th, 2005, 2:07 am

I see the one up front which is obvious... is there another one beneath the car? I thought I checked and didn't see another... but a friend insists there are 2 on almost all cars...

Help?

Thanks,

Phil.

neutral · Post by **neutral** » October 18th, 2005, 4:54 am

You definitely just have the one O2 sensor on your '92 4 cyl - same as on my '95 RS. IIRC, the addition of a second O2 sensor on most 4 cyl cars didn't happen til 1996 when the On Board Diagnostics (OBD) system went from the less sophisticated OBD1 to a more complex OBD2 engine control unit (ECU) that could handle input from the added O2 sensor.

As a side note - For the MX-3 GS V6, pre 1996 models (had OBD1) and two O2 sensors but remember, that's for a V6, not the 4 banger. 1996 and later (OBD2) GS models have four O2 sensors.

yiorta · Post by **yiorta** » October 18th, 2005, 6:57 am

Only one. You will also find it written as "Heated Oxygen Sensor".

Prexus2005 · Post by **Prexus2005** » October 18th, 2005, 10:39 pm

alrighty. Thanks guys. =)

Phil.