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The side fans on my C8 are running extremely loud, and it's definitely not normal. I was just at the Tail of the Dragon and Bowling Green with five other C8s, and mine was the only one screaming the whole time. When I park and shut the car down, the fans speed up even more and run at very high RPMs for about 8 minutes before turning off.
Has anyone else dealt with this? It’s a 2022 HTC with 10k miles and a freshly installed Borla ATAK. It started at the beginning of the season; the exhaust went on right before the trip, but I'm not 100% sure if the fan issue started right before or right after that. The car runs between 170°F and 190°F, so it isn't overheating. There is no check engine light or codes, and the dealer is completely stumped.
Um, for clarity:
Is the fan spinning when hot and parked louder than the other 5 vettes' spinning fans?
Or are the fans running longer than the others?
Do you hear the noise while driving?
Is the sound of the spinning fans similar to the other 5 or an abnormal sound?
Freshly installed exhaust, a suspect install mishap.
I have not dealt with this or have any direct experience with this scenario.
Stumped dealer
FWIW bad bearing, broken blade, component contact, debris seems possible.
Perhaps it is a driving style that uses higher, longer rpm, resulting in more heat?
Because of the exhaust, I could look toward interference or alignment.
I would also inspect the coolant system to ensure there are no air bubbles and the correct fluid level.
Has anyone else dealt with this? It’s a 2022 HTC with 10k miles and a freshly installed Borla ATAK. It started at the beginning of the season; the exhaust went on right before the trip, but I'm not 100% sure if the fan issue started right before or right after that. The car runs between 170°F and 190°F, so it isn't overheating. There is no check engine light or codes, and the dealer is completely stumped.
I would start there in your quest to solve the issue. Maybe the sensor that controls the fans is getting affected by the new exhaust.
Issues with sensors can cause this, and there was a thread about it. In that case it was the coolant temperature sensor that also is used for the DIC coolant temperature display. Its failure seemed to trip a default always-on condition for the rear fans. But yours seems to be working (you are reporting normal temps on the dash) so its not that sensor. But it could be a sensor issue. The engine compartment cooling fan circuit also uses a signal from the Engine Compartment Ambient Temperature Sensor. And maybe that was affected or disturbed when you aftermarket muffler system was installed. I'll attach an illustration showing where it is. I have never found any indication that the fans have an internal temperature sensor.
Thank you for the responses. I was leaning that way too. I took the panel out of the trunk to get to the ambient air sensor, checked it out, and it is plugged in. The wires I could see all looked good. I even unplugged it to check, and everything seemed fine.
I just took the car for a ride; the fans didn't turn on at 175°F, but by 185°F they were not screaming. When I parked, they stayed on at a low speed and shut off after about 4 minutes. It was only a 10-mile run with the AC on and switching in and out of Z-mode. I’m going to drive it for an hour or so now to see if it’s temporarily fixed
Thank you for the responses. I was leaning that way too. I took the panel out of the trunk to get to the ambient air sensor, checked it out, and it is plugged in. The wires I could see all looked good. I even unplugged it to check, and everything seemed fine.
I just took the car for a ride; the fans didn't turn on at 175°F, but by 185°F they were not screaming. When I parked, they stayed on at a low speed and shut off after about 4 minutes. It was only a 10-mile run with the AC on and switching in and out of Z-mode. I’m going to drive it for an hour or so now to see if it’s temporarily fixed
If you have a scan tool you can look at the temperature sensor I think. I do not have scan tool, but in the threads about the underbelly air deflectors, forum members are looking at that temperature sensor to see if those deflectors reduce engine bay temperature.
My side fans are incredibly loud
