Metal knocking (clang) sound from rear offside.

[MaxedOut]

Hi folks, 

my 2019 IS300H has developed an odd sound coming from passenger side rear of the car.

It happens intermittently but every time I drive the car. 

It sounds like you are driving over a metallic drain cover or grate kind of clang. (sounds like two bits of metal

clinking together)

I thought I actually was driving over a manhole but it happens so consistently now 

it's def not that.

Taken it to the dealers twice and they just do a health check and send it back to me. 😞

Any ideas what might be causing it? 

 

Many thanks for any insight.

 

 

 

[NemesisUK]

Definitely nothing in the boot? Under the floor?

Loos heat shielding around the exhaust or the exhaust itself, knocking against the underfloor?

[D Johnson]

57 minutes ago, MaxedOut said:

Hi folks, 

my 2019 IS300H has developed an odd sound coming from passenger side rear of the car.

It happens intermittently but every time I drive the car. 

It sounds like you are driving over a metallic drain cover or grate kind of clang. (sounds like two bits of metal

clinking together)

I thought I actually was driving over a manhole but it happens so consistently now 

it's def not that.

Taken it to the dealers twice and they just do a health check and send it back to me. 😞

Any ideas what might be causing it? 

 

Many thanks for any insight.

 

 

 

I had this with my,admittedly much older, 5 series.  I could only hear it when the windows were open and the car was travelling over somewhat uneven ground.  The drain cover thing you describe is an exact match.  Turned out it was the backplate (both actually) fastenings had corroded (not serious but annoying nevertheless because people hear you coming a mile off.  It cost about £100 per wheel for my indy garage guy to strip them down and replace the washers.  I would definitely try and get underneath and give that plate a wiggle to see if that’s your problem.  

[wharfhouse]

When I had a difficult to describe issue on my car one of the Lexus techs at the dealer came out in the car with me so I could show him when the noise happened - once he could hear what I was hearing he took the car back and quickly sorted the issue. May be worth suggesting this to your dealers service department? 

[Barry14UK]

Might be helpful to OP if you could say what it was Lexus found Phil!

[wharfhouse]

8 hours ago, Barry14UK said:

Might be helpful to OP if you could say what it was Lexus found Phil!

It was a problem with the front wheel bearings - I could hear a noise (it wasn't loud) but this wasn't immediately obvious on the short drive Lexus initially did when I took the car in. When I went out with the tech I could point out when I heard it come on - he could then hear it too and tuned into it. Once he had heard it he was able to replicate it and on investigation back on the lift found it was the wheel bearing. Point is not so much the fault found but taking the tech out in the car to hear it for himself can shortcut a lot of discussion trying to describe something in words. 

[Grumps]

When I used to have issues like this, I would find a road near the dealers where I could replicate the issue every time I drove along that road. 

I then took the mechanic out with me so they could hear the noise. They had no excuse on not hearing the noise, but I did have- "oh that's normal sir"

[wharfhouse]

9 hours ago, wharfhouse said:

When I had a difficult to describe issue on my car one of the Lexus techs at the dealer came out in the car with me so I could show him when the noise happened - once he could hear what I was hearing he took the car back and quickly sorted the issue. May be worth suggesting this to your dealers service department? 

BTW it was the dealer that suggested the tech go out with me rather than me having to instigate it which I was very pleased to see. I have seen the techs going out with other customers when I've had my car in for a service too so is something that my local dealer must have found is a good way of helping with problem diagnosis.

[MaxedOut]

Thanks for the replies, really appreciate it!

I had the "it's a normal hybrid noise sir" too. Clearly it isn't as the noise was not present before.

I'll suggest again for the Tech to come out in the car with me. Maybe they will this time 😉

 

28 minutes ago, Grumps said:

When I used to have issues like this, I would find a road near the dealers where I could replicate the issue every time I drove along that road. 

I then took the mechanic out with me so they could hear the noise. They had no excuse on not hearing the noise, but I did have- "oh that's normal sir"

 

[MaxedOut]

11 hours ago, D Johnson said:

I had this with my,admittedly much older, 5 series.  I could only hear it when the windows were open and the car was travelling over somewhat uneven ground.  The drain cover thing you describe is an exact match.  Turned out it was the backplate (both actually) fastenings had corroded (not serious but annoying nevertheless because people hear you coming a mile off.  It cost about £100 per wheel for my indy garage guy to strip them down and replace the washers.  I would definitely try and get underneath and give that plate a wiggle to see if that’s your problem.  

Also spot on D. I can only hear it when the windows are open too. I did explain that to the dealer. I'm not sure what you mean by backplate as I'm not very car techie. I'll mention that next time I take the car in.

Thanks again.

 

 

[D Johnson]

Here is a picture of the back plate which some refer to as the dust plate: 

[MaxedOut]

17 hours ago, D Johnson said:

Here is a picture of the back plate which some refer to as the dust plate: 

Thanks so much D appreciate it! 🙂

I might take the car to an Indy as the local dealer seems so inept.