AngLi

Hello:
I have a 2021 GX460 Luxury with 2100 miles. When I start the car today (cold start 36 degree) I notice there is a knock inside of the car.
is it normal? I attached the noise, sorry for the noise of my stuffed nose. There is a clear knock, ticking, pounding noise. Please adjust your device to higher volume in order to listen.
Thanks
https://drive.google.com/file/d/1r80...w?usp=drivesdk

Ab175

The Google drive link says I must request access to view it. On the topic of the engine knock, I have always noticed it on mine upon a cold start especially in the 30s and 20s. My GX is at 141k now, had it since new, never had any engine issues (knock on wood). Although it is hard to say if this is the same thing you are experiencing.

AngLi

I am sorry, here is the updated link

https://drive.google.com/file/d/1r80...w?usp=drivesdk

Thanks

ASE

Hard to distinguish ... the audio sounds very muffled ... but the sound does not seem to exactly time with engine RPM's. Slowly increase and decrease engine speed between 1,000 - 2,000 RPM's to see if the sound (knock frequency) increases / decreases with RPM's. I assume the sound was recorded while in Neutral at engine idle ... does it change when placed in Drive ?

kode3

I moan and groan when it's cold also....

Mines got a little startup rattle, likely timing chain... but goes away in a nano second. Would you put the camera near the engine and start it up to get some better audio for us arm chair mechanics to "diagnose"?

Lavrishevo

iTrader: (1)

Air pump for the rear suspension

T4Fun

use 93 octane fuel? if not, that may be the reason.

ps23

Does it go away once the engine is warm? I don't think the sound you are hearing is a knock as in pre-detonation. It is normal to hear that at a cold start-up. Most engines do because there are specified gaps and clearances specified to allow for the various metal parts* to expand once the engine is up to operating temperature.
*Mostly the valve train

AngLi

Hello: Has been using 93 exclusively since day one

Lavrishevo

iTrader: (1)

Does not sound like knocking or valve train noise. You would not normally knock when cold anyway. I would go ahead and change your oil. It’s good for the engine to change the first oil out as high levels of metal in the oil from the break-in period act as microscopic sandpaper. The sound is similar to what I hear when the air pump kicks on. This is most likely what you are hearing.

GX365

Hello. I bought my 2023 GX460 in Jan 24 and I'm now having the same after 3k miles. Could you give us a follow up on yours? Did you take yours to the dealer to replace something under warranty? Thanks

thatwasbrilliant

Have the same thing since new 2023 bought last Oct. Only happens when cold and not all the time. Dealer said can't duplicate. Of course they would say this.

Mentioned it to another dealer and said it's plausible it's piston slap.

ASE

Had a 1986 Toyota 4x4 Pickup from new ... knocked on Cold Start ... TSB indicated that Toyota had shortened the Piston Skirt to reduce friction ... knocking would go away after 2-minutes of warm-up. Toyota's position was that the engine would last beyond the warranty period ... the engine went 285,000 miles ... and only expired due to overheating.

Had a 1990 Toyota 4-Runner from new ... 6,000-odd miles in ... it developed rod knock ... muffled on Cold Start ... reduced upon warm-up but was still present ... Dealership refused to acknowledge, but I elevated to the regional manager ... result: long-block was replaced under warranty.

The GX has many more Cold Start noise sources than earlier vehicles ... so best if it can be pinpointed, and pursued with the Dealership until one is satisfied.