On my JDM MY95 wagon I am in the process of replacing my leaking round PS pump with a later model square type.
The old round pump has a sensor in it. Is it essential to fit this in the replacement square one (which does have a cavity into which it could fit) and what is its purpose?

Thanks.

 

I believe it is for ECU RPM compensation, so the ECU can add some revs if you turn the wheel when stationary or manoeuvering at low speed.

 

Thanks for that.
Shouldn't be a problem not being attached then.

 

ive fitted mine an there no problem with out it being fitted

 

It looks as thought that is a pressure sensor as when I took it apart there was what appeared to be a spring loaded piston type set up and a hole into the main pump which allowed fluid through.

I've left it off and no problems apparent.

Thanks for advice.