Powerboost Idle Sound Levels

[daemonic3]

I know there are several threads about Powerboost sounds (reverse tones, pedestrian sounder, whining noise) but I am not trying to defeat or disable anything, I just want to cross-correlate to see if mine is exhibiting normal behavior, WITHOUT searching for a dealer with hybrids on lot to compare.

My truck has 4 distinct idle sound levels (not counting accessory-only mode):

1. Electric: Ready in park, no foot on brake
2. Electric: Ready in park, with foot on brake
3. Electric: Ready in drive, foot on brake (not moving though!)
4. Engine Idle

I took some sound meter 30 second plots. I was in a quiet culdesac, in a 3 car garage (middle) with no car on either side. I rolled down my window and held my meter (phone) stably about 1 foot out the window.

Results:

• My garage ambient: 28dB
• Mode1: ~39dB
• Mode2: ~45dB
• Mode3: ~50dB
• Engine: ~65dB (brake, no brake, drive, didn't seem to matter - RPM was ~1.2k in this instance)

Here are the plots:

(repeated for consistency check)

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[daemonic3]

Now with the data presented, here are my questions where I need your testimonials!

Are your powerboosts all making that same whirring just by being "ON"? I had attributed this to likely fan noise and NOT from the speaker/sounder but want to make sure it is normal. I get +11dB from this in my garage!!

Do your powerboosts have a noticeable increase in sound just by pushing the brake, even when not moving? Seems silly but if it is "arming" the regenerative circuitry then ok, maybe I can understand it. But just want to make sure this is normal...

When shifting to drive, I *think* that is the fake engine noise added on top. To me personally (and my meter), the "ON" whirring and brake noise are BOTH louder than the fake engine noise so it alone doesn't bother me.

Thanks in advance!!

 

[JIMFOUNTAIN]

You did not mention temps and HVAC settings. In Texas with higher temps my powerboost with the AC on but gas engine at 0 RPM is louder than the gas engine idle with HVAC off. I assume the sounds I hear are the fans to move air through the radiator and AC condenser plus the pump/AC compressor running.

My warm idle RPMs are more like 700... 1,200 seems high and is what I see at cold start. Do you have Eco Idle On? That bumps RPMS while in park. Was the engine cold? Ambient temperature cold?

See whether HVAC settings make a difference.... Also whether a warm engine makes a difference.

I will try testing mine with the HVAC off. Already seeing 80s so will test tomorrow AM before the heat.

 

[daemonic3]

You did not mention temps and HVAC settings. In Texas with higher temps my powerboost with the AC on but gas engine at 0 RPM is louder than the gas engine idle with HVAC off. I assume the sounds I hear are the fans to move air through the radiator and AC condenser plus the pump/AC compressor running.

My warm idle RPMs are more like 700... 1,200 seems high and is what I see at cold start. Do you have Eco Idle On? That bumps RPMS while in park. Was the engine cold? Ambient temperature cold?

See whether HVAC settings make a difference.... Also whether a warm engine makes a difference.

I will try testing mine with the HVAC off. Already seeing 80s so will test tomorrow AM before the heat.

You're right! I forgot to mention, I turned all audio and HVAC off, as I had hoped that was the noise but it wasn't.

Temperature was roughly 60F.

On the RPM's, it likely turned on ICE on that start due to cold. I hadn't been driving it, and I was actually expecting an electric start but it went ICE. It started at roughly 1.2kRPM in the graph, then I was waiting for it to shut off and go electric so I can do more experiments. It went down to 0.8kRPM for a bit, then up to 1.5kRPM (I assume this is because I have Eco Idle enabled). I gave up waiting and shut it off, and my next couple starts were electric. As noted, the dB was roughly the same at the range of RPMs I mentioned (which surprised me).

That does raise a good question - it may have been running something to warm up the battery. I know I've walked past teslas in parking lots on cold days and you can hear them running some sort of fan while sitting empty. So maybe if I drove around and parked it may be quieter... Of course, this doesn't quite help the noise level overnight if I'm trying to camp quietly!

 

[JIMFOUNTAIN]

OK.. Results w/o the use of a meter...

I have the same experience with no HVAC. ICE RPM 0:

1. Electric: Ready in park, no foot on brake - making some "whirrring" sounds.. hard to describe but not very loud. Coming from under the hood?
2. Electric: Ready in park, with foot on brake - definite "buzz" sound coming from under the bed. Occurs anytime brake is applied in any gear.
3. Electric: Ready in drive, foot on brake (not moving though!) - Adds more electric motor kinds of sounds.. even though not moving. Get those sounds plus the beep if shifted to reverse.
4. Engine Idle - sure.

I don't think your experience is unique.

Running the 7.2 KW generator to support a 3800 kw 240 volt heater... the ICE cycles off and on and there is always some fan noises from under the hood. Probably cooling the inverter or something. Having just experienced days with power in Austin Tx and using my standalone gas generator to power the house.... the F150 is much quieter. And much more powerful.

I am not concerned about noise in a campground from running the generator to support an RV/whatever... the F150 generator function is quieter than most campground generators.

Jim

 

[daemonic3]

I am not concerned about noise in a campground from running the generator to support an RV/whatever... the F150 generator function is quieter than most campground generators.

Oh for sure!! *And* as a bonus, I don't think people will know the difference between "he started the truck then decided not to drive it" sound versus "that's a generator and it's not generator hours!!!" hahaha. I think we will get some leeway on noise.

The whirring is tolerable to *me*, and thank you for confirming my truck is not abnormal! It is my wife that has misophonia for things like fan noises and I can already predict her complaints about this whirring from (under?) the truck.

I planned to do some tailgating at my daughter's volleyball tournament in Reno soon. No parents allowed in the facility, so I wanted to set up a TV in the back of the truck and have others bring chairs. We can stream the zoom meeting (there will be a camera on a connected iPad at the court) to my TV. I am very worried that the whirring will be a no-go with the wife, but it depends on the ambient noise of our surroundings!

 

[Doublet]

There shouldn't be much "whirling" while the brake is not pressed. So I believe that your wife shouldn't really notice it while standing outside with just the pro power running.

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