Noise issues - AC and clunk?

Hello everyone, we have owned a Volt for 2 years now and recently purchased a MS. First, hands down, the Model S is FAR superior to the Volt, or any other vehicle on the road (IMHO); and electric driving is pure awesomeness. That said, there are a two problems, both noise related that the MS has and Volt doesn't.

1) The A/C compressor fan in MS is MUCH louder than the Volt; and MS does not cool with noticeable differences. The big problem seems to be some type of ramp-up period when the the a/c first kicks on, it sounds like a 4 bannger ICE for two minutes or so. Once ramp-up is finished, the Volt and MS noise is about the same.

2) At low speeds, along our driveway and private road, there is a clunk from the rear of MS when you let off the go pedal. This only happens at speeds between 5-18mph. Our private road is 1/4 mile long with three speed bumps a gate, so we hear this clunk 4 to 5 times each time we leave or return home...along w/every parking lot in between. In the Volt, its perfectly silent. Tesla Rocklin test drove the car and says this relatively common and there's nothing to worry about as long as it does not get louder.

Had MS been our first electric vehicle, we would have dismissed both noises as minor trade offs for driving electric, but they are not. Anyway, I'm sure Tesla will eventually fix these issues and they are (relatively) minor, however they do currently exist.

FWIW, we are keeping the Volt until MIII is available...

Cool, I'll run to the service center tomorrow or Thursday and report back afterwards...

Update: Just back from the service center, the clunk is indeed the drive unit and will be replaced. They'll check out the noisy a/c ramp-up when the drive unit is replaced...fingers crossed it can be replicated. To improve the odds of replication, I may wait for a heat wave to schedule service since it only happens on super hot days.

Electricfan - I am doing the same thing as you, switching back and forth between the Volt and MS. Like you, I have found there are times when it's more enjoyable to drive the Volt and a big plus personally, it has satellite radio!

MKnox - The U-joint analogy is dead on, this is exactly the sounds. Unfortunately, it's become louder and happening at higher speeds now too...

The drive unit was replaced last Thursday at the Rocklin SC, the clunk is gone. We also had the humming sound that others have reported at high speeds, but didn't realize it was a problem until the sound was eliminated.

We are being told they did replicate the loud A/C ramp up and it's normal. I didn't fully understand the verbal explanation, here's the written explanation:

HVAC is operating normal. AC will be louder on hot days or while supercharging, this is normal. AC will get softer once the set temperature in the cabin has been reached, or supercharging has stopped.

No car is perfect so we'll live with the loud AC ramp, fortunately it only lasts for a couple minutes. I'm sure the engineers are well aware of this issue and will find a solution before M3 is released, if not sooner.

Overall, the SC was great and the warranty experience exceptional!

AmpedRealtor said:

The AC ramp up noise is normal, but Tesla has issued a service bulletin to install an acoustic blanket and a new bracket. That is being installed at owner request regardless of whether the AC is "normal" or not. Did you request that retrofit? Don't accept the service center's answer if they haven't at least gone to the effort of dampening the sound with the service bulletin. This is free of charge and is available to all Model S owners.

Click to expand...

No, I didn't request the retrofit, but it was mentioned as a solution by the person who scheduled the repairs. The service advisor took over once I arrived for the work to be done and he was pretty hum-ho about the noise. For now I'll live with it, but if the car goes back in for additional service I will ask for the retrofit for sure. Thanks for the help.