Which Oxygen sensor is code P0142 "O2 Sensor Circuit Malfunction (Bank 1, Sensor 3)"

12-19-03, 23:42

Have a 1998 626-LX-V6, 80,000km.

Recently the check engine light came on, and the code pulled was:

P0142 "O2 Sensor Circuit Malfunction (Bank 1, Sensor 3)"

Does anyone know which oxygen sensor this is, and where it is located on the car?

Thanks.

**Einstein** · 12-20-03, 10:40

Bank 1 is usually the front... O2 sensor is in the front header pipe.. easy to get to, and a 15 minute job to change.. Buy a universal 4 wire 18mm sensor, and splice the old connector back on... Mazda ones are too expensive, and are the same article, just comes with a connector on the end.

Bear in mind, the rear one, (which normally fails first) will not be far behind, so it may be wise to change the rear one at the same time.

Get to it from the back of the right wheel arch.. it's a complete PITA to do.

John

12-20-03, 12:30

Ok, so it's from the front cylinders, thanks.

Does the UK version have four O2 sensors or just two?

I'm still a little unsure about the "Sensor 3" part... is that the sensor after the cat or before?

And with comedian mode on, if so, why is it called 3 and not 2? ;>

**Einstein** · 12-21-03, 5:27

UK models.. 92 - 97 have to sensors... J-spec imports have an extra one just after the CAT.

Our UK 626 V6 ended in 94... never been as good since.

John