hi fellow Lexusan. i bought this 2015 F sport with 42k miles two months ago. This is my first Lexus and i was counting on the realiability that it's known for. But after driving the car and reading the forum i'm not so confident anymore since cars these days are fond to have minor/major break down no matter which brand you go with. That said, ever since i got this Lexus this engine noise accompany with a soft, constant vibration that you can feel sitting in the car putting your hand on the arm rest. The noise and vibration only show up when i put the car in D (under load) - as you can hear from 13 seconds in the video onward. The first 13 seconds the engine in Neutral (no load). the noise is really like a tractor engine. it's knocking with a deep humm and it's loud, you can hear sitting inside the cabin.
i checked service History on Lexus Drivers and it shows the car had oil change every 10k miles (which something i don't recommend) and no other remarks but regular wear and tear. Date-of-First-Use is August/2015. Clean Carfax history as well. So fellas, please help me identify this noise. Thank you in advance!

 

I have a same noise on a driver side under a slight acceleration though, i can hear it from the cabin i feel like driving a tractor lol, it is started after it’s 100k miles, but my car is 07” IS 350, it’s basically same engine.

 

Is this what's called knocking noise?

 

Use a scan tool to see if there are any stored DTCs.

 

A lot of the noise is dampen by the engine cover. I can hear the DI system in the background but a lot of engine noise sounds normal. What happened to the engine cover?

OCI is subjective as well but we won't go into that.

 

Most of the sound sounds normal, most of the sound seems to be coming from the high pressure fuel pump. The metallic tapping noise from the driver side doesn't sound normal to me.

 

i took the cover off so i can locate that humming noise. i check the oil level and it's fine. no smoke coming out of the exhaust either. Im hoping it's not "rod knocking" but would a Scan tool give me the result if it was? if it was Rod knocking, do you think Lexus will cover under "powertrain" warranty, since i still have 3 months left till August. Thank you

 

That sounds normal to me. As someone has mentioned, the diesel tractor noise is coming from the high pressure fuel pump (which is normal for this GS 3.5 engine).

 

hi, thanks for the reply. what about the constant vibration when i put into D? it feels like a mass rotating but out of balance from the engine bay, transfer into the cabin. i can feel it at every stop light. and the car only has 43k miles. i dont think this is normal (for a Lexus at that).

 

I would take it in and get a proper diagnosis.

 

Sounds just like my 2016 GS350.

 

took it to Lexus and left it over night for them to run diagnostic, found nothing and said "it's normal" - of course! they said hooked up to Techstream any everything but everything is normal. good thing they didn't charge me anything though. i might have to try another stealership and see what happens. i also notice when i turn on the AC, the vibration goes away and idle a little smoother. bad roller belt bearing?

 

Doesn’t sound abnormal. But the vibration shouldn’t be felt inside the cabin.

 

How's the oil look like? Clean or dirty?

Found this, maybe it will help.

https://www.bellperformance.com/blog...-engine-noises

 

Thanks for the info. So i added a whole bottle of Seafoam to the crankcase and it seems to quiet down alot! Now get me thinking its the lifters noise. How do you get Lexus to do something about this? How can a car with regular maintance at 45k miles already has lifters noise. So much for Lexus reliability