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Old Jun 28, 2025 | 02:23 PM
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Default Overheats

My 2004 Corvette overheats when sitting for 10 minutes. But when I take off go down the road the temperature comes back to normal it's only when I sit at red lights. Does anyone have any suggestions? I did read that it could be a fuse it could be the the fan or it could be a clogged radiator thank you
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Old Jun 28, 2025 | 02:34 PM
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Maybe radiator needs to be cleaned due to restricted airflow…you can start there.




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Old Jun 28, 2025 | 02:59 PM
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How hot? 230, 260?
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Old Jun 28, 2025 | 03:17 PM
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Originally Posted by Laura2004
My 2004 Corvette overheats when sitting for 10 minutes. But when I take off go down the road the temperature comes back to normal it's only when I sit at red lights. Does anyone have any suggestions? I did read that it could be a fuse it could be the the fan or it could be a clogged radiator thank you
It's not a fuse.
Open the hood. Start the car and turn on the air conditioner. Look at the fans. Are they spinning? If so it's probably not the fan.
Get under the car and look where the air flows up into the radiator. Do you see a bunch of stuff there restricting air flow? Remove it carefully. For a thorough cleaning you can remove the top plastic part above the radiator and A/C condenser and carefully spray water backwards through them. There are tools to make this easier.
Good luck.
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Old Jun 28, 2025 | 03:25 PM
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These things run hot by design. 220 or more seems normal. In my experience while stopped in traffic turning the A/C on starts the fans and drops the temperature.
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Old Jun 28, 2025 | 03:43 PM
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Originally Posted by Dads2kconvertible
It's not a fuse.
Open the hood. Start the car and turn on the air conditioner. Look at the fans. Are they spinning? If so it's probably not the fan.
Get under the car and look where the air flows up into the radiator. Do you see a bunch of stuff there restricting air flow? Remove it carefully. For a thorough cleaning you can remove the top plastic part above the radiator and A/C condenser and carefully spray water backwards through them. There are tools to make this easier.
Good luck.
thank you!
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Old Jun 28, 2025 | 03:43 PM
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Originally Posted by h8snow
how hot? 230, 260?
250
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Old Jun 28, 2025 | 03:46 PM
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Originally Posted by DDaaryl
These things run hot by design. 220 or more seems normal. In my experience while stopped in traffic turning the A/C on starts the fans and drops the temperature.
I was sitting at drive thru for 7 minutes I noticed my air conditioner was not that cold. I looked at the have our said 240 and got almost up to 260. I turned the air off . Going down the road or did cool down.
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Old Jun 28, 2025 | 03:47 PM
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Originally Posted by C5 Diag
Maybe radiator needs to be cleaned due to restricted airflow…you can start there.




https://youtu.be/J02kTZblkMA?si=HF_zQsU3wl7LethQ
Thank you
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Old Jun 28, 2025 | 03:51 PM
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Originally Posted by Laura2004
I was sitting at drive thru for 7 minutes I noticed my air conditioner was not that cold. I looked at the have our said 240 and got almost up to 260. I turned the air off . Going down the road or did cool down.

If the AC is not cold it sounds like the fans not working…I’d find an auto electric shop and take your car there.
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Old Jun 28, 2025 | 05:25 PM
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Yeah, sounds like the fans are not working.
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Old Jun 28, 2025 | 05:30 PM
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Default Cleaned

Originally Posted by Dads2kconvertible
It's not a fuse.
Open the hood. Start the car and turn on the air conditioner. Look at the fans. Are they spinning? If so it's probably not the fan.
Get under the car and look where the air flows up into the radiator. Do you see a bunch of stuff there restricting air flow? Remove it carefully. For a thorough cleaning you can remove the top plastic part above the radiator and A/C condenser and carefully spray water backwards through them. There are tools to make this easier.
Good luck.
I went under the front of car, the radiator did have debris on top and sides. I cleaned it up with a special fan brush . Went thru a drive thru did not overheat. Did a little drive pulled over and sat there with engine running for 10 minutes. Did not overheat. Thank you for the advice and I'm hoping this does the trick.
Thank you much appreciated!
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Old Jun 29, 2025 | 12:39 AM
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Moved to C5 Tech for more assistance.
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Old Jun 29, 2025 | 09:02 AM
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Originally Posted by C5 Diag
If the AC is not cold it sounds like the fans not working…I’d find an auto elctric shop and take your car there.
Thank you
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Old Jun 29, 2025 | 09:16 AM
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Originally Posted by h8snow
How hot? 230, 260?
YES! OP would help his cause if he defined "overheats."
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Old Jun 29, 2025 | 10:54 PM
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Originally Posted by Laura2004
I went under the front of car, the radiator did have debris on top and sides. I cleaned it up with a special fan brush . Went thru a drive thru did not overheat. Did a little drive pulled over and sat there with engine running for 10 minutes. Did not overheat. Thank you for the advice and I'm hoping this does the trick.
Thank you much appreciated!
One more thing to check- there should be a 3 piece plastic air dam under the car to direct air towards and up into the radiator. It's a wear item, kind of. They can scrape, especially if the car is lowered. Some people pull them off. If they are missing I suggest you obtain a set and install them.
https://www.corvettepartscenter.com/...dams-episode-7
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Old Jun 29, 2025 | 11:02 PM
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Originally Posted by Dads2kconvertible
One more thing to check- there should be a 3 piece plastic air dam under the car to direct air towards and up into the radiator. It's a wear item, kind of. They can scrape, especially if the car is lowered. Some people pull them off. If they are missing I suggest you obtain a set and install them.
https://www.corvettepartscenter.com/...dams-episode-7
Thank you and I will definitely check it out!
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Old Jun 30, 2025 | 08:00 AM
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Originally Posted by Dads2kconvertible
One more thing to check- there should be a 3 piece plastic air dam under the car to direct air towards and up into the radiator. It's a wear item, kind of. They can scrape, especially if the car is lowered. Some people pull them off. If they are missing I suggest you obtain a set and install them.
https://www.corvettepartscenter.com/...dams-episode-7
Would make sense if the engine was overheating at cruise. In this case, the engine is overheating at idle....so the splitter does come into play.
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Old Jun 30, 2025 | 12:01 PM
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Originally Posted by lucky131969
Would make sense if the engine was overheating at cruise. In this case, the engine is overheating at idle....so the splitter does come into play.
I think you meant does not come into play?
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Old Jun 30, 2025 | 06:39 PM
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Originally Posted by Dads2kconvertible
I think you meant does not come into play?
Yep, that is what I meant.......does NOT come into play.
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