EVAP VSV voltage please

[markweatherill]

Hi,

my car is based on Yaris mechanicals with the 2NZ-FE engine.

I measured the voltage at the EVAP VSV connector with the ignition on and there was 10.5V. Not enough to open the valve reliably.

Can someone meter their VSV connector and see if that is normal behaviour please? I'd expect 12V or nothing at all but not anything in between.

And if anyone knows when the VSV should or shouldn't be opening, it would be handy to know.

Thanks!

[CTScott]

The VSV is pulsed by the ECM and the frequency increases as the RPMs do, so with a DC voltmeter the voltage will be lower at lower RPMs and will approach battery voltage at full throttle.

[markweatherill]

Many thanks. I tested it by sucking on the pipe with the engine running. Sure enough there was a regular pulse and a taste of fumes.:smile: