Coolant Temp Sensor kicking my rear.

[dmaisenh]

I have the Oxygen Sensor crows foot tool but I can not find a way to get it on the sensor.
I have seen threads were people say they just break the plastic portion of the sensor off and use a socket but I don't have a 22mm socket and really don't want to break the sensor just to find I still cant get it out.
Working totally blind under the intake here.
After reading various posts I thought this would be a minor PITA but it is turning into a major one.

And just so everyone knows I am replacing this because INPA reports my coolant temp as 202 C which is obviously not the case, my coolant out temp is 44 C

Any tips or tricks?

[effduration]

But a cheap 22mm open end wrench and cut it in half..reach up under manifold from the back..it doesn’t take much torque to loosen

[JimLev]

Not trying to be a smart ass but what don’t you get a 22mm socket? One can never have too many tools.

[dmaisenh]

Not trying to be a smart ass but what don’t you get a 22mm socket? One can never have too many tools.

The socket is not the issue, I don't want to destroy the sensor only to find out I still can't get it out.

[JimLev]

Get a deep well socket. Won’t the socket fit over the plastic end?

[dmaisenh]

Not enough room under the manifold to get a deep socket on it. I tried another O2 sensor socket that is straight and taller, no go.
I just got back from Harbor Freight where I got a cheap set of short line wrenches that include a 22mm. They are 8 inches long and if that proves to be to long I also picked up some fresh hack saw blades.

[energizedmortal]

Not enough room under the manifold to get a deep socket on it. I tried another O2 sensor socket that is straight and taller, no go.
I just got back from Harbor Freight where I got a cheap set of short line wrenches that include a 22mm. They are 8 inches long and if that proves to be to long I also picked up some fresh hack saw blades.

Can try a hand sized vice grip, deep socket 10 mm on one of the handles for leverage. Tough angle I replaced one when I had the intake off to do heater pipes, ccv, starter, and intake manifold gasket.

[Ed CT]

Your '99 set up is a bit different than my '98, but can you get an adjustable wrench on an O2 socket top, or directly on the O2 sensor? All you need to do is break the seal in a few degrees' turn.

[ross1]

That is a bitch of a spot. My thoughts are to disconnect the wire and use a 12pt box wrench. You'll need a stubby or cut one off. There is an insulation panel on the firewall you could remove for some more clearance to swing a wrench. take off the cabin air inlets and weather strip at the cowl. The insulation panel is attached with 4(?) 1/4 turn fasteners and a couple clips along the top edge.
Be careful of the nearby plastic coolant pipes.
Have fun.

[Twistytee]

https://www.bimmerfest.com/threads/diy-528-engine-block-coolant-double-temperature-switch.798265/

[ross1]

https://www.bimmerfest.com/threads/diy-528-engine-block-coolant-double-temperature-switch.798265/
DIY is for m52. OP has M52tu engine, coolant temp sensor at rear of the head.

[TiagE39]

Here's my very detailed writeup on how to do this. (https://www.bimmerforums.com/forum/showthread.php?2420972-M52TU-Coolant-Temp-Sensor-Success)