Hi all,

I recently purchased a used 2018 IS350 F-Sport with approx 85K Kms and I have just noticed a strange noise that seems only to start to occur under the following conditions:

1. Condition 1:
   • Start the car (cold or warm)
   • Shift the transmission from P to D - no strange noise at this point (at least not that I can hear)
   • Shift the transmission back from D to P
   • The strange noise occurs, like a clanking type noise (see attached video of the suspect noise), note the noise seems to reduce and becomes barely audible after one minute or so.
2. Condition 2:
   • Start the car (cold or warm)
   • Shift the transmission from P to D - no strange noise at this point (at least not that I can hear)
   • Release the brake
   • As the car starts to move forward, a strange noise occurs, like a clanking type noise (see attached video of the suspect noise in question)

I have attached a video of the noise (this happened under condition 1 above)

I have no problems with gear shifts, they seem smooth and no issues with how the car drives.

I have no warning lights on the dash.

I've had a 2012 IS350 for the past 7 years and no such issues as this one.

I am keen to see if anyone has experienced this before or can shed some light.

 

Hi,
The video shows a continuous noise. Then you said something about a clanking noise. From my experience if it's just one clanking noise, then it must be the parking brakes/rear discs assembly.
But, if you were writing about a continuous noise, like in the video, then I would go to a mechanic shop (preferably Toyota/Lexus trained) to get to the bottom of the issue, like yesterday.

 

Hi, thanks for the reply and yes i'm writing about the noise in the video, that noise eventually goes away after a minute or so. I'm trying to get it booked in with the closest Lexus dealership.

 

Someone on another forum suggested it could be the vacuum pump, I did a bit of research and found a whole bunch of info with other people with the same problem across several Lexus models from 2018 onwards.The link below is the most detailed thread I found on this issue if anyone else is interested, basically from what I understood Lexus was advising this customer that the noise was from the vacuum pump when the engine is cold the oil "slaps" around that area making the knocking type noise you hear. When the oil warms up the noise subsides.

Here is the link to the above-mentioned thread: Strange engine noise - Page 2 - ClubLexus - Lexus Forum Discussion

Note, I also easily reproduced the noise when pumping the brake pedal when in park/neutral. The good news seems to be that the noise is not harmful or an indication of an issue, but more of a design flaw of the vacuum pump that causes the oil to "slap" around when pumped in, and this is more apparent when the oil is cold. I will still take it to Lexus for confirmation, but the info I have come across so far does ease my mind.

Also, I found this Lexus TSB on the issue: MC-10247804-9999.pdf (nhtsa.gov)