ct4v bw exhaust valve rattle

[bl4ck_wng]

just curious, does anyone's exhaust rattle at low rpms when the valves are all the way open --

is there anything I can do about it?

 

[bl4ck_wng]

it never bothered me much, but now i can't seem to not notice it

 

[strohw]

Mine did. I honestly just ignored it because my last two vehicles had a bit of a valve rattle as well.

 

[Beamz27]

Yes it’s either the valves or the LF4 waste gate issue. Both annoying as hell

 

[dwduck]

Is the wastegate issue an actual problem or just an annoying noise? I noticed it also.. Usually it means that the turbos are going bad but this is on a brand new car!

 

[DesertRJ]

I get some rattle as well. Do my best to ignore it lol

 

[dwduck]

Same here but maybe @WONT TAP can clarify what this rattling noise is and if it causes any power deficiencies or problems? I usually notice it from the front of the car while accelerating with windows down after a cold start and less noticable when the car warms up. Sounds like a plastic zip tie or like a little ball shaking in a metal can.The dealer says turbo wastegate rattle but it's "not a big deal."

 

[WONT TAP]

The dealer says turbo wastegate rattle but it's "not a big deal."

Agreed. This is a non issue.

 

[MDM]

Here is a picture of the valve in place and then removed. There is a coil spring that goes between the electric motor and the mechanical part of the valve. The spring is not shown in the picture. It seems that the spring is designed to keep tension on the valve, so it doesn't rattle. This is on a 5BW but I'm guessing it would be the same. Hope this helps.

 

[Jdeee]

Is this the same rattle everyone is talking about?

 

[flipray]

Is this the same rattle everyone is talking about?

No, thats the wastegate squeel. People have replaced turbos under warranty for it and it came back. My guess is the housing hole for the wastegate flap shaft isnt smoothly bored.

 

[Beamz97]

Is this the same rattle everyone is talking about?

Mine does this and it’s easy to hear if you rev it in the garage. Fuckin drives me nuts. Sounds like shit

 

[Dalyons03]

I took mine in for this noise and they replaced the starter. Said it was contacting the flywheel. Dramatically better and still has some noise but I no longer feel like my car is a POS lol

 

[Throat Yogurt]

I brought my car in for a metallic rattle from the exhaust valves that you could hear at low RPM and revving just off idle. They replaced the exhaust system from the cat back and it solved the problem. 2022 4BW, approx. 30k miles.

 

[Dalyons03]

I brought my car in for a metallic rattle from the exhaust valves that you could hear at low RPM and revving just off idle. They replaced the exhaust system from the cat back and it solved the problem. 2022 4BW, approx. 30k miles.

Was noise at the rear of the car where the valves are located?

Mine sounds up front per say

 

[Throat Yogurt]

Was noise at the rear of the car where the valves are located?

Mine sounds up front per say

Yes, my noise was coming from the valves themselves at the rear of the car. It was hard to hear with the windows up, but very obvious from outside the car or with the windows down in a parking garage.

 

[Dalyons03]

Thanks for input, mine is definitely up front underneath. I think it’s the watergates these are famous for. Likely will just deal with it instead of having turbos changed to have it come back anyway.

 

[Beamz97]

Thanks for input, mine is definitely up front underneath. I think it’s the watergates these are famous for. Likely will just deal with it instead of having turbos changed to have it come back anyway.

There’s a fix that’s hard to find but there’s a TSB somewhere to use spring cup washers or something like that and it keeps tension on the wastegates and fixes the rattle. That’s how they fixed it on my ATS V. It went from sounding like I was dragging tin cans to gone. If you do some google searching you might find it in some of the threads.

 

[Dalyons03]

There’s a fix that’s hard to find but there’s a TSB somewhere to use spring cup washers or something like that and it keeps tension on the wastegates and fixes the rattle. That’s how they fixed it on my ATS V. It went from sounding like I was dragging tin cans to gone. If you do some google searching you might find it in some of the threads.

Thanks I have seen it before and was under impression it was for earlier LF4 LF3 engines. Worth asking to see if it’s an option. It drives me nuts lol

 

[ngoni]

Thanks I have seen it before and was under impression it was for earlier LF4 LF3 engines. Worth asking to see if it’s an option. It drives me nuts lol

I think this is it.

https://static.nhtsa.gov/odi/tsbs/2018/MC-10139275-9999.pdf