hades281

Hi all -

I've noticed a noise coming from my car (2014 IS350 RWD) that sounds like a light, irregular rattle, when the engine is running in the 3500 - 4500 RPM range. I don't hear it necessarily under load, but if I am in manual mode in a lower gear, and let off the throttle, I can hear it.

The best way I can describe the noise is like a bowl of rice crispies (rapid and random), only slightly louder. You have to listen for it, the road/traffic should be quiet, and if you get back on the gas, the intake noise that's plumbed into the cabin pretty much covers it up. I can also hear it in Park or Neutral.... I've wondered if it's a loose heat shield, or an exhaust issue, but I can't hear it standing next to the car or with my head under the hood. I only hear it from the cabin. The rhythm of the noise is irregular.

Does anyone hear this?

I don't think it's ping/detonation, since that usually shows up under load, is much louder and has a decidedly metallic sound to it compared to what I'm hearing.

TheShaddix

Had the same exact issue with mine, sometimes it went away. But mine was around 6-7k. After I replaced the intake that went away though.

hieuhuynh

I have something similar. I believe it's either the secondary cats or resonators, something is loose inside. I have PPE headers and is far more apparent at 2500 to 4500 rpm. I hope the new JoeZ exhaust will help in that regard.

hades281

Are either of you planning to take your cars in to have this looked at? I'll probably mention it at the 5k service.... I tried to look up TSBs for the car to see if Lexus had one for this issue, but I think I need a subscription to TIS in order to see what TSBs might be out there.

CobraGSF

iTrader: (2)

So just noticed today I'm getting a slight rattling/crackling sound at 4000-5000 rpm. And I really don't know what it is...being that I don't really push the car to often I only heard it today. Any idea of what it could be? Any other experiences? I did hit a lovely sized pothole today. Thanks northeast weather. Maybe that knocked something out of place?

TheShaddix

I used to have the same problem on mine (fsport 350), some something was loose in the engine bay by the passenger side. It did that with the stock intake though, once I replaced that I don't hear any noise anymore. I'm running a Joe z pipe with the stock airbox. And since it's much quieter, that noise would definitely be louder if it were still there. I guess it's due to the intake sound amplifier on the stock pipe. But this is my theory. You could be experiencing something else, who knows.

hades281

I have this same problem exactly (started a thread about it a few days ago). Help!!

Crackling is the perfect way to describe the noise. When I rev the car in P or N, I can still hear it in the cab with windows up, but I can't hear it outside over the normal engine and exhaust sounds. I've stood over the engine bay and had my GF rev the car, and I still can't hear it. Only in the cab.

I've put the car on ramps and checked for loose heat shields, banged on the exhaust with my fist... I can't find anything loose.

https://www.clublexus.com/forums/is-...-4500-rpm.html

Does anyone have access to Lexus TSIBs, who can check and see if one has been issued for this?

Glashub

It's sound like a rattling catalytic converter type sound from the passenger seat side. I have it but not consistently and it certainly doesn't sound dangerous or overly intrusive when it does sound off. The problem is I probably wouldn't be able to replicate it at the dealership.

hades281

Easist way for me to replicate the noise, is to shift into manual mode on a quiet road and gradually increase the speed. Once I'm into 3500 - 4000+ RPM with light load on the engine, it's pretty clear.

onepointon

My 350 F-sport does that same exact thing, sounds like its coming from the passenger side. There are no TSIBs on the issue. It bothers me but I haven't gotten around to digging too much into it. I peaked around my engine bay when I did the 5k on my car and didn't see anything that stood out. I was trying to decide if I feel like its in the interior or not the other day.

Didn't know other people were having the same issue. I am going to run it by my FTS next time I talk to him.

Glashub

It sounds exhaust related on my car.

dbs600

Anyone else experiencing a rattle / high pitch noise between 5,500 and 6,500 rpm?

Wasn't previously present, now happening consistently and not normal.

Difficult to tell where it's coming from; passenger-side, maybe?

Thanks. :|

TheShaddix

Are you on stock intake?

hades281

Crackling noise? There are a few threads about this issue (a good sign for us, that Lexus will have enough affected cars to find out about it and identify the fix).

https://www.clublexus.com/forums/is-...0-5000rpm.html

https://www.clublexus.com/forums/is-...-4500-rpm.html

hades281

Glashub - I agree, to the ear it sounds exhaust related. TheShaddix said it went away in his car when he swapped intakes, and the "noisemaker" is on the passenger side of the engine.

The only way for us to pinpoint whether the noisemaker is at fault, is to remove the noisemaker from the intake (and plug the hole).