Just ordered a new engine temp sensor for my 94 WRX. Manual says simply remove old sensor and replace. However I have found a few threads stating big fluid leaks. Can I simply remove without leaks? Also, a mechanic suggested a while back that I might be able to create a vacuum by clamping the main fluid hoses with grips. Any one elaborate on this? or how to do it?

Cheers

 

I changed the coolant sensor on my 93 WRX a few months back.

To reduce spillage, the engine was stone cold and I syphoned out as much as I could out of the header tank before undoing the old sensor. Water will spill out as you change the sensor, but I simply topped up the header tank afterwards and haven't had any problems.

You need to make sure that the hose to the header has no air in it, and just keep an eye on the level over the next few days. I think I needed to top up a few mls after first running the engine, but that was it.

Good luck, as getting to the sensor is a complete nightmare!!

 

Cheers mate. Knuckle stripping here we go!