Odd CGTS40 Sound (no, not the ticking 🤣)
In first gear at a steady 2500RPM there is a distinct, rhythmic, low frequency pulse. Somewhat similar to a flat tire sound. You can also hear it in second at similar RPM, but not as clearly. It’s possible this has been around from day one but, being at 23,000 miles, I doubt I never noticed. You can even feel it ever so slightly, but the car is rock solid at speed - vibration free etc - so it seems to be a creeping at low speed thing. I was thinking possibly some kind of exhaust back pressure? Any insights are appreciated.
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J-Dub
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Nothing is coming to mind.
To rule out the exhaust maybe try both forcing the flaps open all the time and forcing them closed and making drives back to back.
If it was wheel bearing it may vary when you swerve right vs swerve left. Does a swerve cause or diminish the noise?
To rule out the exhaust maybe try both forcing the flaps open all the time and forcing them closed and making drives back to back.
If it was wheel bearing it may vary when you swerve right vs swerve left. Does a swerve cause or diminish the noise?
1957 VW Beetle
2004 VW R32
2021 Porsche Cayman GTS 4.0
2004 VW R32
2021 Porsche Cayman GTS 4.0
Bearing came to mind as well. I’ll have to try swerving under the known conditions. I’ll also try various exhaust settings.J-Dub wrote: Mon Nov 27, 2023 5:24 pm Nothing is coming to mind.
To rule out the exhaust maybe try both forcing the flaps open all the time and forcing them closed and making drives back to back.
If it was wheel bearing it may vary when you swerve right vs swerve left. Does a swerve cause or diminish the noise?
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Tom
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If your car were a 944, I'd say to check your CV joints. They tend to first start making noise at low speeds, low load, cruising -- and you can provoke more noise by letting off the gas when going slow, or by making tight circles slowly with the steering wheel locked to one side (then the other). Look for leaking boots and/or grab the axles and see if there is much play. Not familiar enough with your car to say if the symptoms carry over, but I figure it's worth a look. You might also drive past someone slowly when the noise is happening to see if its origin is more obvious from the outside.FLCAYMAN wrote: Mon Nov 27, 2023 4:55 pm In first gear at a steady 2500RPM there is a distinct, rhythmic, low frequency pulse. Somewhat similar to a flat tire sound. You can also hear it in second at similar RPM, but not as clearly. It’s possible this has been around from day one but, being at 23,000 miles, I doubt I never noticed. You can even feel it ever so slightly, but the car is rock solid at speed - vibration free etc - so it seems to be a creeping at low speed thing. I was thinking possibly some kind of exhaust back pressure? Any insights are appreciated.