engine temps
Thread Starter
Racer
Joined: Nov 2006
Posts: 491
Likes: 10
From: Atlanta Ga
engine temps
Do your temps rise when ac is running? Just noticed that running about 198 - 201 on highway with ac off and went up to 220 with ac on? Fans are programmed to both turn on at 195, have stock thermostat. Ac on in traffic temps climb to 230+, ac off stays about 200. outside temps in HOT Lanta has been 98 - 102.
Have checked for blockages but have not filled with fresh coolant (1 1/2 yrs)
Have checked for blockages but have not filled with fresh coolant (1 1/2 yrs)
Le Mans Master
Joined: Aug 2009
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Likes: 1,058
From: Chester County Pennsylvania
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Do your temps rise when ac is running? Just noticed that running about 198 - 201 on highway with ac off and went up to 220 with ac on? Fans are programmed to both turn on at 195, have stock thermostat. Ac on in traffic temps climb to 230+, ac off stays about 200. outside temps in HOT Lanta has been 98 - 102.
Have checked for blockages but have not filled with fresh coolant (1 1/2 yrs)
Have checked for blockages but have not filled with fresh coolant (1 1/2 yrs)
Melting Slicks
Joined: Jun 2008
Posts: 2,283
Likes: 16
From: Katy Tx
also check your rubber air dam center section -- mine got very floppy after 65k miles of scraping stuff - I think it got to where the air just
pushed it back. It broke off recently and the temps jumped even more right away...but when I put the new one on, temps were back to below what they were before it broke. Now 195 at 70mph in Hot Houston. Ran around 220 with no air dam. Its very easy to replace -- 2 10mm bolts.
pushed it back. It broke off recently and the temps jumped even more right away...but when I put the new one on, temps were back to below what they were before it broke. Now 195 at 70mph in Hot Houston. Ran around 220 with no air dam. Its very easy to replace -- 2 10mm bolts.
Drifting
Joined: May 2006
Posts: 1,616
Likes: 1
From: Minnesota
Wow your fans must run all the time having them both some on at 195. Consider changing it so the low speed comes on at say 196 and the high speed one at 206 or something. I have heard they can wear out fast if you get aggressive with the settings like you did.
For me with a stock thermostat I run at 192-194 at highway speeds and usually not above 200 in stop and go. That is with a clean radiator and good clean coolant. For the record 220 is not that hot. The stock fan settings I believe won't kick on the high fan until 222 or somewhere in there.
Spend some time on your back with a air compressor hose cleaning the fins. If you haven't done that before you will be amazed at the junk that comes out.
For me with a stock thermostat I run at 192-194 at highway speeds and usually not above 200 in stop and go. That is with a clean radiator and good clean coolant. For the record 220 is not that hot. The stock fan settings I believe won't kick on the high fan until 222 or somewhere in there.
Spend some time on your back with a air compressor hose cleaning the fins. If you haven't done that before you will be amazed at the junk that comes out.
Pro
Joined: Dec 2009
Posts: 688
Likes: 18
From: Seattle Wa
It's funny you say this, I have noticed when I kick the ac on my temp seems to drop a few degrees.
I haven't replaced my airdam yet and I see 220-230 in stop/go on a hot day. At speed on the freeway It's 180-195.
I haven't replaced my airdam yet and I see 220-230 in stop/go on a hot day. At speed on the freeway It's 180-195.
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Race Director
Joined: Oct 2007
Posts: 14,108
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From: 4th on the list of top 100 in USA Ga.
Mine was running about 225 with A/C on in 100 degrees before,I did the License cover mod and added holes in the fog light coves and it now runs about 212-215 in 100 degrees,It draws in a lot more air now.
Drifting
Joined: Apr 2008
Posts: 1,283
Likes: 1
From: Eureka California
Wow your fans must run all the time having them both some on at 195. Consider changing it so the low speed comes on at say 196 and the high speed one at 206 or something. I have heard they can wear out fast if you get aggressive with the settings like you did.
For me with a stock thermostat I run at 192-194 at highway speeds and usually not above 200 in stop and go. That is with a clean radiator and good clean coolant. For the record 220 is not that hot. The stock fan settings I believe won't kick on the high fan until 222 or somewhere in there.
Spend some time on your back with a air compressor hose cleaning the fins. If you haven't done that before you will be amazed at the junk that comes out.
For me with a stock thermostat I run at 192-194 at highway speeds and usually not above 200 in stop and go. That is with a clean radiator and good clean coolant. For the record 220 is not that hot. The stock fan settings I believe won't kick on the high fan until 222 or somewhere in there.
Spend some time on your back with a air compressor hose cleaning the fins. If you haven't done that before you will be amazed at the junk that comes out.
Installed a screen beneath the radiator to keep most of the junk out, They do suck in a bunch of stuff.I just ordered a remote fan control from SacCityCorvette so I'll have more control over when the fan kicks in during slow hot weather travel here in Nevada. It just seems like 220-225 is kinda hot, probably not but it'll make me feel better to keep it cooler.
Drifting
Joined: Oct 2006
Posts: 1,773
Likes: 2
From: San Diego CA
The fans turn off when speed reaches higher than 35 mph. At that speed the air dam is forcing more air through the radiator than the fans. Your freeway speed/temps suggest your air dam is OK....
220-230 on a hot day in stop and go traffic with AC on is not unusual. The OEM high speed fan setting doesn't kick on until 235.
Of course, it never hurts to clean the radiator out. These bottom breathers ingest a lot of junk!
FYI.......
FROM THE SERVICE MANUAL
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).
Good Luck.....
