As a 2008 Impala owner I’ve become well acquainted with a specific part failure. Typically, it’s not expensive to correct (as long as it’s not one under the dash) but it can be inconvenient and over time I’ve had to replace two of them multiple times each.
For those that have experienced this problem I decided to post some photos that help reveal where the failure occurs.
The first photo included in this post shows an unopened actuator.
The next photo shows the actuator split open:
When I opened the actuator several of the damaged teeth fell out of the casing. A closer photograph reveals that several teeth from a gear are missing:
I suspect that all of these that have failed in my vehicle would show the same problem. Could this problem be solved by using metal gears? Perhaps.
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when i tried to replace one last night, no key in ignition, i plugged power wire to actuator before installing. The rod that goes into actuator began spinning. THAT is the problem—electricity running to actuator causing the gears to spin when there is no blend door to open. the added pressure breaks the teeth. Chevy knows this but of course would rather us continue to buy parts over and over again
It amazes me. GM is so bent on the idea of all electric cars in the future but yet they can’t even invent a car where the user can open and close HVAC doors with their actuators. The parts are extremely dirt cheap online but its the labor that gets you. I’ve heard of people paying up to $750 for the driver side actuator replacement. For a part that cost $20. The average person likely will have to pay $750 because it is beyond difficult to replace.