zzok

Hey everyone

First post here, long(ish) time lurker.
So I own a 2018 LC500h, bought a few months ago with around 95.000 km (60k miles) directly from a Lexus dealer in Europe.

It has this "mysterious" little noise coming from the front, seemingly but not surely on the passenger side. It's kind of hard to describe and virtually impossible to record so please bear with me and this long post as I'm trying to explain when and how it occurs.

It is a really (and i mean really) soft whirr / rattle/ "trrrt" that appears in specific conditions:

- Mainly when pressing the accelerator pedal; very apparent around 2-3k rpms; can't hear it at higher rpms but engine noise might hide it though;
- it is continuous and constant but once the foot is off the pedal, it instantly stops
- It is ALSO there when braking, but in a weird way not as consistently (75% of the time?)
- it's there when the combustion engine engages but ONLY IF accelerator is pressed, as opposed to not being there when in EV mode; although a harder press on the accelerator turns on the combustion (it's quite sensitive) so not exactly sure here
- when the auto is shifting gears but ONLY when accelerating/braking, as opposed to:
- there being NO sound when changing gears manually from the paddles/stick, whatever the rpms or speed, without pressing any pedal.
- it does not appear when car is stationary with the engine on in neutral, idling/revving; also not there when trying to launch with both pedals pressed
- the slightest press on the accelerator and sometimes the brake pedal while the car is running (over 10km/h) and it's there
- it feels it gets even softer after the car heats up for a bit, but still very noticeable
- it is basically exactly the same intensity/volume no matter the speed, rpms etc. just a soft, silent, continuous "frrrrrrrrrt"
- has been described as a "loose plastic", "probably the air filter", "a loose air hose", by different people that have been in the car so yeah.. As a side note, no one noticed it without me pointing it out. Also nothing visible in those regards.
- not louder with windows down, if anything it's a bit less noticeable
- not sensitive to turning the A/C or ventilation on/off/higher etc, not sensitive to driving modes (it's the same in Eco/S+)

As i've said it's a really soft noise and the local Lexus dealership service mechanic of course is saying that he can't hear anything. Told me to come back when it gets louder. The shop is located in a high traffic/loud city area so it's quite hard to distinguish, I can give him that. But on a quiet mountain road it is fairly easy to hear.

The car runs perfectly fine otherwise, great performance, great range, there's absolutely no other apparent issue. No weird clonks and bonks, no uneven tire wear, smooth gear shifts, no wheels heating up excessively/asymmetrically. Had a complete checkup at the dealership, hybrid system check, full 100K km service done in advance, also changed transmission oil. It had the front brakes fully serviced by the dealership just before I bought it (rotors/pads have less than 1k miles on them).
Still, this mystery sound is driving me a bit nuts.

I know there aren't many LC500h's around here but maybe it's not H specific so someone ran into this issue or has an idea. I plan to also take it to a local non-Lexus shop but i know for a fact they haven't worked on an LC before (alas neither did the Toyota/Lexus service..) so any kind of guidance and information helps.

Anyway please excuse the long post, thanks so much for reading this far!

mcomer

Might you be hearing the Pedestrian Warning sound that comes from a speaker under the grille?
Normally off when stopped, loudest with first moving, changes tone with speed, quits when the IC motor starts.