Trying to track down a noise that I thought was the fuel tank issue.

If I drive in normal mode, cruising 7th gear, temperature runs about 228 to 232° in my ‘15CS.

When I drive in manual and sport mode, temp drops to around 204°.

I never hear the noise when I’m in manual/sport mode.

But it put it in regular cruising mode, and as the temperature climbs, the noise appears.

Today after I heard the noise, I went back to manual/sport, watched the temperature drop, and the noise disappeared.

I definitely need to do some more testing, but does anybody have thoughts on this ?

 

I'm now headed into my 3rd week waiting for the dealer to sort out what my '18 Targa puked coolant out all over the highway. Water pump's been replaced now, as has the "valve block". I'm guessing there's some fancy rearranging going on with how the coolant is routed through the engine. Wonder if that's related to what you're seeing re manual vs pdk?

 

My sound is a squeak, kind of like dense Styrofoam rubbing against something, only over bumps.

Seems to be about right under the sports Chrono clock, but hard to pinpoint.

From what I understand, the temperature fluctuation is normal between regular mode and manual/sport.

 

Sport mode opens the air-water radiator above the engine in my 991.1 and drops the temps by about 20 degrees just as you describe. So I guess the noise from the dash area is likely an unrelated coincidence.

I had a similar "up front under dash" noise when i first got my car. It was intermittent and I thought it must be related to cold outside temps. After months of chasing it down, I took it to a mechanic at my dealer early in the am when it was really cold. He went for a short test ride and heard the sound, and on inspection found a plastic part under the rubber cover in the frunk, drivers side, was loose. I am not sure what it was but it never reoccured after he found it.

 

Interesting.

I find it odd that it only happens in regular mode when I’m cruising, and if I’m in sport/ manual, I don’t hear it after temp drops.

Outside ambient temperature doesn’t seem to make any difference.

Took me a little while to make the correlation, but I think I am onto something.


just wish I knew what I was onto? 🤓.

sunroof open, manual/ sport, and music if all else fails!

maybe somebody else had similiar experience.

 

I would look under the hood and pull all the plastic out and see if something isn't loose. I'm thinking you're not hearing it when in sport mode because the car is typically louder because of the higher RPM and shift points. I would bet it's near your battery or something simple thats loose.

 

Thx.

When I first start driving, it never makes the noise.

It’s only when the car gets up to full temperature (like 225-230) that I hear it.

Once it cools off, it disappears.

I know it sounds crazy, but it seems to be something temperature related going on.

just trying to figure out, logically, what that could be. I was hoping someone smarter than me could explain it. 🤣