C5 Temperature Problem
Thread Starter
Melting Slicks
Joined: Jun 2003
Posts: 2,767
Likes: 0
From: Indianapolis IN
C5 Temperature Problem
On the way home today my coolant temp reached 230 degrees. It didn't seem to want to go any higher than that but that's definitely about 20 degrees higher than usual. I first glanced at my temp gauge when I caught a slight smell of anti-freeze. I checked under the hood and there doesn't appear to be any leaks. My heater didn't seem quite as hot either. Today was a warm day (about 81 degrees) but even it 100 plus heat, it usually doesn't go above about 220.
What could it be? Thermostat? Low coolant? Heater core (let's hope not)?
Thoughts? Thanks for any insight.
What could it be? Thermostat? Low coolant? Heater core (let's hope not)?
Thoughts? Thanks for any insight.
Former Vendor
Joined: Jan 2008
Posts: 4,202
Likes: 1
From: Greenville SC
Hi, there are a few things to check out. 1st, Do you have a 160 degree thermostat? If not you need one. 2, Check for trash, leaves and whatever between the radiator and ac condensor, clean all that out.
3rd, make sure the center airdam is function properly. 4th, when is the last time you had the system flushed?
If you would like to call me directly please do, we help people out all over the US from the Corvette Forum (Parts-Service) what ever you need. Just ask for Mike
or Joey
Thanks
Mike Yeager
Eastcoast Performance & Corvette
1-864-404-1776
3rd, make sure the center airdam is function properly. 4th, when is the last time you had the system flushed?
If you would like to call me directly please do, we help people out all over the US from the Corvette Forum (Parts-Service) what ever you need. Just ask for Mike
or JoeyThanks
Mike Yeager
Eastcoast Performance & Corvette
1-864-404-1776
Thread Starter
Melting Slicks
Joined: Jun 2003
Posts: 2,767
Likes: 0
From: Indianapolis IN
Thanks Mike. Thanks for the info!
There is no debris between the radiator and AC.
How do I know if I have a 160 degree thermostat?
I got the C5 used and I have never changed the coolant but I don't know if the previous owner did.
How would I know if the center air dam is functioning properly? It appears to be connected properly and such. Any other tests?
Sorry for all of the questions! Thanks for any other suggestions!
There is no debris between the radiator and AC.
How do I know if I have a 160 degree thermostat?
I got the C5 used and I have never changed the coolant but I don't know if the previous owner did.
How would I know if the center air dam is functioning properly? It appears to be connected properly and such. Any other tests?
Sorry for all of the questions! Thanks for any other suggestions!
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Le Mans Master
Joined: May 2007
Posts: 5,383
Likes: 6
From: hagerstown md
St. Jude Donor '08-'09
Sounds like your thermostat is stuck in the OPEN position.
When it sticks open, coolant runs through the system too fast and doesn't spend enough time in the radiator. So it isn't cooled sufficiently.
When it sticks open, coolant runs through the system too fast and doesn't spend enough time in the radiator. So it isn't cooled sufficiently.
Thread Starter
Melting Slicks
Joined: Jun 2003
Posts: 2,767
Likes: 0
From: Indianapolis IN
Thanks. That's what I'm thinkin' too.
I've seen serveral posts on WHICH thermostat to buy but does anyone have a how-to on how to change it? It looks pretty simple but I just want to make sure there's nothing wacky that I'm missing. I'd definitely prefer not to drain the coolant too.
I've seen serveral posts on WHICH thermostat to buy but does anyone have a how-to on how to change it? It looks pretty simple but I just want to make sure there's nothing wacky that I'm missing. I'd definitely prefer not to drain the coolant too.
Former Vendor
Joined: Jan 2008
Posts: 4,202
Likes: 1
From: Greenville SC
It was very nice talking with you Saturday on the phone, its alot easier to explain things verbaly for me anyway. Did you check your fans to make sure they both come on at around 212.
If they did not both come on check all the connections 1st.
Call me Monday if you want the HP 160 thermostat.
Thanks
Mike Yeager
1-864-404-1776
If they did not both come on check all the connections 1st.
Call me Monday if you want the HP 160 thermostat.
Thanks
Mike Yeager
1-864-404-1776
Le Mans Master
Joined: Aug 2000
Posts: 5,808
Likes: 1
From: Sierra Foothills California
Had exactly the same symptoms! I replaced the thermostat and the temp. sensor ($14.00 located over #1 plug). Everythings normal again. Don't know which was at fault, but I suspect the thermostat.
Thread Starter
Melting Slicks
Joined: Jun 2003
Posts: 2,767
Likes: 0
From: Indianapolis IN
It was very nice talking with you Saturday on the phone, its alot easier to explain things verbaly for me anyway. Did you check your fans to make sure they both come on at around 212.
If they did not both come on check all the connections 1st.
Call me Monday if you want the HP 160 thermostat.
Thanks
Mike Yeager
1-864-404-1776
If they did not both come on check all the connections 1st.
Call me Monday if you want the HP 160 thermostat.
Thanks
Mike Yeager
1-864-404-1776
Someone must have piggybacked my thread. Anywho, I'm still trying to decide if it's a problem. I took her out on Saturday and the temp never got over 215.
All that's to say, I still might call ya and if I need a new stat, I'll be getting a 160 from you.
Thanks for the help that you provide everyone here.
Le Mans Master
Joined: Feb 2002
Posts: 6,937
Likes: 21
From: Waldorf MD
I see no problem, see below:
C5 Cooling Fans Operation
The low speed cooling fan is commanded on when the coolant temperature reaches 108°C (226°F). It is turned off if the coolant temperature lowers to 104°C (219°F). The high speed cooling fan is commanded on when the coolant temperature reaches 113°C (235°F). It is turned off if the coolant temperature lowers to 108°C (226°F). When the A/C is on and the coolant temperature reaches 85°C (185°F), the low speed cooling fan will be turned on at vehicle speeds less than 56 kPh (35 mph).
BUT, always check for debris in front of radiator when having cooling problems, these C5's are bottom breathers and act like street vacuum cleaners (leaves, plastic bags, etc)
C5 Cooling Fans Operation
The low speed cooling fan is commanded on when the coolant temperature reaches 108°C (226°F). It is turned off if the coolant temperature lowers to 104°C (219°F). The high speed cooling fan is commanded on when the coolant temperature reaches 113°C (235°F). It is turned off if the coolant temperature lowers to 108°C (226°F). When the A/C is on and the coolant temperature reaches 85°C (185°F), the low speed cooling fan will be turned on at vehicle speeds less than 56 kPh (35 mph).
BUT, always check for debris in front of radiator when having cooling problems, these C5's are bottom breathers and act like street vacuum cleaners (leaves, plastic bags, etc)
Last edited by Oldvetter; Apr 27, 2009 at 04:38 PM.
