1MZ-FE (Estima) O2 sensor

richardmayes, Dec 4, 3:45pm
Had my check engine light analyzed, and it's a dying O2 sensor.

I have seen what I presume is the head of the sensor, on the LH side of the exhaust manifold, and am tempted to do the labour of fitting the replacement sensor myself to save a buck.

Are there any pitfalls or obvious traps for young players with fitting these? I hear o2 sensors can be delicate and need to be looked after, I was expecting to have to handle it like it's a headlight bulb.

[I'm not a mechanic but do my own oil changes, brake pads etc so I own just enough spanners to be dangerous. ]

franc123, Dec 4, 6:22pm
Yep, unless you have the correct socket to undo it (this is a slotted tube socket made for the purpose) with a bar and extension, or the hex on the sensor is not obscured by heat shielding AND there is enough space to swing a normal length 22mm spanner in there it could be a mission to remove.

richardmayes, Oct 14, 3:56pm
Thanks Franc

Yes I believe if I remove all of the black plastic undertray and go at it from underneath, there should be just enough room to get a bit of a swing on a spanner.

It's definitely the tightest packed engine room I've ever owned. I'm used to the sort of cars where if you drop a washer or a socket, it just falls straight through onto the floor.