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Drifting
Joined: Jul 2015
Posts: 1,844
Likes: 375
From: San Jose, CA
Coolant temp shoots up driving at highway speeds but not idling? The opposite of a common issue, so your radiator probably isn't dirty. Is your coolant level adequate? Have you burped the coolant? Is your water pump leaking or showing other signs of failure?
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
How do you know that the engine is not over heating?? Have you used any measuring devices to check the engine block temps?? Purchase a cheep inferred laser temp tool and measure the block and water pump thermostat housing when it overheats (GAGE shoots up)
The coolant sensor and connector are on the head just below #1 spark plug. Remove the connector and inspect the connector and wiring harness. If it were me, I would change out that sensor.
YES,, If the sensor reports overheat to the PCM, the AC will shut off as its programmed to do to remove that extra load from the engine and cooling system.
TRUST ME, if the engine was actually overheating, it would not just magically POP back into specs when you went below 60MPH. It takes a LONG tome to cool the overheated block back down once it reaches critical temps.
IF, you are low on coolant and there is steam in the heads, it could act that way.
BURP the cooling system using the steam crossover pipe fitting bolt at the front of the heads and see if the block is full of coolant. If you crack that fastener loose,(DO NOT FULLY REMOVE THE BOLT IF THE ENGINE IS HOT!!) you should see coolant flow out. If there is air in the system it will escape and then the coolant will flow out!
BC
The coolant sensor and connector are on the head just below #1 spark plug. Remove the connector and inspect the connector and wiring harness. If it were me, I would change out that sensor.
YES,, If the sensor reports overheat to the PCM, the AC will shut off as its programmed to do to remove that extra load from the engine and cooling system.
TRUST ME, if the engine was actually overheating, it would not just magically POP back into specs when you went below 60MPH. It takes a LONG tome to cool the overheated block back down once it reaches critical temps.
IF, you are low on coolant and there is steam in the heads, it could act that way.
BURP the cooling system using the steam crossover pipe fitting bolt at the front of the heads and see if the block is full of coolant. If you crack that fastener loose,(DO NOT FULLY REMOVE THE BOLT IF THE ENGINE IS HOT!!) you should see coolant flow out. If there is air in the system it will escape and then the coolant will flow out!
BC
Melting Slicks
Joined: Sep 2011
Posts: 2,258
Likes: 544
From: Appleton WI
Try turning your heater and fan on high when driving above 60MPH. Does that help your issue? What did you recently do to your car?
Have you physically looked under the car? Maybe something is stuck under the car and flips up at speed to block airflow or your AC condenser is blocked / plugged.
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Have you physically looked under the car? Maybe something is stuck under the car and flips up at speed to block airflow or your AC condenser is blocked / plugged.
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Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
I normally do one (doesn't matter what side) but, if I am not fully satisfied, I will crack open both one at a time. Pick what ever bolt is easiest to get to.
Melting Slicks
Joined: Sep 2011
Posts: 2,258
Likes: 544
From: Appleton WI
Doesn't look like your spoiler has any openings; correct? Did you remove the center air dam during install? If yes to one or both above, you aren't pushing any air up to the radiator. The heater trick I mentioned above would likely confirm that as would removing the spoiler (which I think would be a pain).
Edit: Openings look small in the spoiler. Didn't have a good view on my phone. Retracted comment about Z06 openings as they are for cold air to intake.
Edit: Openings look small in the spoiler. Didn't have a good view on my phone. Retracted comment about Z06 openings as they are for cold air to intake.
Last edited by 3sACROWD; May 29, 2019 at 10:45 PM.
Thread Starter
Advanced
Joined: Feb 2019
Posts: 66
Likes: 4
Doesn't look like your spoiler has any openings; correct? Did you remove the center air dam during install? If yes to one or both above, you aren't pushing any air up to the radiator. The heater trick I mentioned above would likely confirm that as would removing the spoiler (which I think would be a pain).
Edit: Openings look small in the spoiler. Didn't have a good view on my phone. Retracted comment about Z06 openings as they are for cold air to intake.
Edit: Openings look small in the spoiler. Didn't have a good view on my phone. Retracted comment about Z06 openings as they are for cold air to intake.
Burning Brakes
Joined: Apr 2017
Posts: 1,055
Likes: 104
From: Romeoville, IL
I can verify this on mine. My air dam broke off and had a similar issue. I put on a new air dam and issue went away. With out the air dam my temps were all over and high. Air dam on and I am back to normal temps.
