Never saw myself as much of a mechanic, but here I am replacing a vacuum actuator that helps direct the airflow in a motor vehicle. This is chapter two of a five-part series on the Holden VY Series II. I tried a few things to get it working as best as possible. Some things I succeeded at, others I didn’t. Join me on this weird journey of retro car repair!

We found that the airflow kept diverting to the windscreen when other modes were selected, particularly under engine load above roughly 2000 RPM. The mode actuators run on inlet-manifold vacuum, with a tank and check valve keeping a reserve when that vacuum drops. I was hoping that replacing one actuator would rule out a possible leak. We picked up a “Commodore Vacuum Actuator Air Vent Control VT VX VY VZ Genuine Holden NEW” for $77 shipped. The hoses, check valve, vacuum tank, other actuators and solenoid pack were still possible places to investigate. Plenty left to chase!

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