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Normal Operating Sounds

tesla.com

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Re: Normal Operating Sounds

#131

Post by alliao »

Kirby64 wrote: post #22
jacquesm wrote: post #17

Earlier quoted context omitted.

What is the cause? Thermal expansion? I have a room in my attic that can make really loud bangs on hot summer nights (enough to scare the crap out of me when I am concentrating on something and do not expect them) when it contracts again after a day in the heat. The root cause there is stick slip: the thing doesn't move for a long time due to its weight so tension builds up and then suddenly it will shift a little an…

Similar mechanism as your attic noises. There's a giant metal plate on the bottom of the thing, so all the heat generated while it's supercharging (in a very cold environment) causes that 'snap' which makes a loud noise. Same thing happens if you've ever heated up a thin metal baking sheet. It'll 'snap' from one position to another and make a horrible racket. Same thing apparently happens if you are heavy on regenera…

thanks! I've heard the pops during my winter trips but never associated with thermal expansion! Always thought I'd hit some animals or debris on the road.

Re: Normal Operating Sounds

#132

Post by kccqzy »

smt88 wrote: post #105
kccqzy wrote: post #36

Earlier quoted context omitted.

I've driven the Ioniq 5 and I can easily hear a high pitched motor whine at speeds between 45 and 60 mph. I cannot hear any noise below 45 or above 60, other than the intentional pedestrian warning sound. I suspect as I age my ability to hear such high pitched whine will be gone.

Motor whine isn't a weird sound and it's unsurprising Hyundai doesn't have an FAQ page to explain it. I suspect many of these noises are due to Tesla's notoriously poor build quality.

I agree it isn't weird but it bothers me much more than the engine noise of an ICE car.

Re: Normal Operating Sounds

#133

Post by [deleted] »

londons_explore wrote: post #103
JasonSage wrote: post #82

Earlier quoted context omitted.

This is 100% correct. For those curious, the coolant around the engine block can boil and flow upwards after the engine is off, and the coolant circulation system is designed to handle this pattern. You can observe this yourself if you overfill your coolant and take it out on a hot day, the excess hot coolant will bubble up and run out for a good while after the engine is off. I second the advice that if the engine i…

It's also a common cause of breakdowns... The fan normally cools the radiator, but the temperature sensor is on a coolant hose. Since the engine is stopped coolant isn't flowing so the fan isn't cooling the same thing the sensor is sensing, which means it can end up running for 30 mins or more. Since the fan can be 20 amps or so, you can easily kill old car batteries due to this effect. User comes back after an hour…

[deleted]

Re: Normal Operating Sounds

#136

Post by xg15 »

dralley wrote: post #28
bigyikes wrote: post #7

This one is pretty cool and definitely surprised me. > Motor Humming or Whirring when Navigating to a Supercharger … > In some circumstances (such as cold weather), it is normal for the motor(s) and components to make noise, such as humming or whirring as it generates heat to warm the Battery. Super cool that the motors can be used for things other than moving the vehicle. It reminds me of how ESCs for RC vehicles us…

My understanding is that high-end residential heat pumps (e.g. Mitsubishi HyperHeat) will do this at lower temperatures as well. If the temp drops into the zone where the heat pump starts losing effectiveness (which on such systems is still pretty low, supposedly mine provides the full heat rating down to around 0F), they can run the blower motor in a less efficient regime to supplement the heat pump with a bit of re…

I find it interesting that you can find stuff like this even in biology: When you shiver in cold weather, your body is basically doing the same.

Re: Normal Operating Sounds

#137

Post by crashmat »

stephen_g wrote: post #89
josephcsible wrote: post #71

Earlier quoted context omitted.

How can anything be <100% if producing heat is the goal? Where would the rest of the energy be going?

I’m not sure what they mean about crypto miners or computers (mentioning cinebench), basically all the energy going in should be turned into heat so that should be near enough to 100% efficient. Where else would the energy be going? Sure, there will be a bit of RF power (Wi-Fi and some EMI) and depending on the device, a bit of light (LED indicators, monitor backlight) but that should be tiny compared to the energy t…

Won't light heat things up by bouncing around anyway?

Re: Normal Operating Sounds

#138

Post by HPsquared »

l33tman wrote: post #115
bb123 wrote: post #100

Earlier quoted context omitted.

This is due to a phenomenon called heat soak which is where the engine temperature increases above normal for a time after it has been switched off due to the lack of coolant flow. The fan is coming on to aid cooling the engine/engine bay to reduce the effect of heat soak. With carburettor fed engines it is sometimes advised by the manufacturer to allow the engine to idle for some time after running it at high RPM. T…

same issue with projector lamps, the fan is kept on for a while after you shut them off

And ovens.

Re: Normal Operating Sounds

#139

Post by actionfromafar »

bb123 wrote: post #100
spike021 wrote: post #41

Earlier quoted context omitted.

I have a relatively analogue car (Subaru BRZ) and there are times when you shut it off on a warm day and then randomly about ten mins later a radiator fan kicks on. I guess it's to help cool down but I don't remember exactly what the manual says. Basically it's cool how cars do things largely on their own sometimes to stay within certain parameters.

This is due to a phenomenon called heat soak which is where the engine temperature increases above normal for a time after it has been switched off due to the lack of coolant flow. The fan is coming on to aid cooling the engine/engine bay to reduce the effect of heat soak. With carburettor fed engines it is sometimes advised by the manufacturer to allow the engine to idle for some time after running it at high RPM. T…

Also turbo charged engines can greatly benefit from running idle for a minute. I learned the hard way. (Had to replace the turbo.)
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