What is this and what is its purpose?

[spf_lexus]

99% done hooking my 99 UZ into a 92 body and I have this sensor/unit im not too sure of.

Toyota part #25860-50100 listed as "vacuum switching assembly". Whats its purpose?

What is it supposed to be connected to? It has a vacuum line mounted on top of TB with a 2 foot vacuum line that I think runs across the manifold but not too sure. There just isnt any obvious place where it could reach. I'v never seen this motor fully installed in person so its sort of a mystery.

Any help appreciated,

Sean

 

[Zuffen]

Most likely the vacuum purge unit.

It connects the manifold to the charcoal canister and when the engine is under vacuum it operates to suck any fuel fumes out of the canister into the engine to burn them.

There should be a wiring tail for it directly opposite the t/b.

 

[spf_lexus]

ok well that was easy. Thanks Rod.


If I delete my canister will I get a CEL? Since its exposed to atmosphere I wouldnt think taking the line off would do much since the canister has an open drain at bottom dropping right onto the road. Then again it does have a smaller vacuum line (small 1/8th inch I.D.) routed to the purge valve. Once shes idling idling i'll mess around with it

 

[Zuffen]

Other than perhaps increasing your carbon footprint I can't see it will affect the way your engine runs.

I don't run one as my aftermarket ECU can't control it.