Hello All,

I have a 2021 LS 500. Intermittently when starting the car I hear a loud roar from the rear/muffler area. Maybe 1 out of every 10 starts over the past year. Once the car is running no issues. I have not reported it to the dealer yet but I'm starting to hear it more often. Any ideas on root cause? Muffler bad or other component? I plan on letting Lexus Service know the next time I bring in the car for maintenance.

Thanks in advance.

 

I do not own a LS500 (yet) but what you are describing may be just a symptom of a cold start. Depending on the engine temps, the amount of fuel delivered and idle setting from the computer will make vehicles louder during the first 30 seconds or so. This "cold start" is normal and quiets down as the engine temp warms up, as well as the idle gets lower.

 

If you don't mind could you record a video of it to better help us understand better.

 

Thanks for the reply, remake. I'm still suspicious that it's something to do with the exhaust system / muffler. I'll chat with my service advisor during the next service visit.

 

Hello bigblack06,

Thanks for the message. This is very intermittent therefore recording a video would be hit or miss. More miss based on it's infrequency.

 

And you don't have a hybrid correct? I want to say muffler but not sure, let us know what the dealer says.

 

My LS 500 is not a hybrid. As soon as I talk to the service manager I'll update the post. Thanks.

 

I would bet this is the explanation. Frankly, I would just enjoy the loud roar!