Overheating issue, any ideas?
Thread Starter
Heel & Toe
Joined: Aug 2014
Posts: 21
Likes: 6
From: Murrieta CA
Overheating issue, any ideas?
I have a 2014 Z51 and have an intermittent overheating issue that only occurs during certain circumstances, but I can repeat the issue.
Driving around in traffic is not a problem. The problem occurs on longer distance drives. If I start my drive on the freeway at high speed and drive about 30 miles (the car will probably be around 190-195 F), and then get into stop and go traffic, the fans will not turn on and the car will overheat. A simple restart of the car will kick the fans back on.
It only happens after high-speed (60+MPH) driving for an extended period of time (20+ mins) and then getting into bumper-to-bumper traffic right after (<10 MPH).
Any ideas on what could be causing this? Clearly the computer is not telling the fans to turn back on after the temps start getting past 200?
Driving around in traffic is not a problem. The problem occurs on longer distance drives. If I start my drive on the freeway at high speed and drive about 30 miles (the car will probably be around 190-195 F), and then get into stop and go traffic, the fans will not turn on and the car will overheat. A simple restart of the car will kick the fans back on.
It only happens after high-speed (60+MPH) driving for an extended period of time (20+ mins) and then getting into bumper-to-bumper traffic right after (<10 MPH).
Any ideas on what could be causing this? Clearly the computer is not telling the fans to turn back on after the temps start getting past 200?
Moderator emeritus
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From: Jacksonville Florida BWO Dayton, Cincinnati, Bloomsbury NJ, Cincinnati
2015 C7 of the Year Finalist
I swear that I had the same damn issue a few weeks ago on my 2014. Driving on Interstate, 10 miles or so, hit a major traffic jam and started creeping along in bumper to bumper traffic and the damn temp gauge rolled up almost into the red bar. Pulled over, stopped the engine waited 2 or 3 minutes, restarted the engine and the temp needle plummeted down to 200 in the blink of an eye. My fans were screaming as the temp fell.
Sounds the same, huh?
Elmer
Sounds the same, huh?
Elmer
Heel & Toe
Joined: Jun 2017
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Not sure if this is the issue but I had an over heating problem. Later on my c7 overheated and released the coolant from the bypass valve. Turned out to be the coolant reservoir cap. After that it kept leaking coolant from a hole in the radiator, which was then replaced by the dealer. Since then I haven't had a single issue with overheating.
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From: Jacksonville Florida BWO Dayton, Cincinnati, Bloomsbury NJ, Cincinnati
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Coolant levels are full. No loss of coolant. If there were, then the overheating would happen most if not all of the time.
Elmer
Elmer
Safety Car
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Sounds like some kind of weird programming glitch with the ECM control of the fan. There have been several reports since early on in the C7 generation of oddball random overheating events when either stationary or in very slow traffic.
Since the OP has found a way to trigger the behavior consistently maybe GM will get to the bottom of this problem.
Since the OP has found a way to trigger the behavior consistently maybe GM will get to the bottom of this problem.
Racer
Joined: Oct 2004
Posts: 432
Likes: 49
From: Southern Maryland
Sounds like you guys have narrowed it down to the cooling fans coming on (or not). Does this happen when the a/c is on? Just a suggestion to better trouble shoot this.
Thread Starter
Heel & Toe
Joined: Aug 2014
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From: Murrieta CA
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Moderator emeritus
Joined: Jun 2001
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From: Jacksonville Florida BWO Dayton, Cincinnati, Bloomsbury NJ, Cincinnati
2015 C7 of the Year Finalist
I'm pretty sure the AC was on as I'm in Florida. No cooling fans were heard until the car was shut off and restarted. It sounds like it doesn't matter.
I started a thread but it happened to me right after I updated the NAV map.
https://www.corvetteforum.com/forums...-to-260-a.html
Elmer
I started a thread but it happened to me right after I updated the NAV map.
https://www.corvetteforum.com/forums...-to-260-a.html
Elmer
Last edited by eboggs_jkvl; Dec 28, 2017 at 06:50 PM.
Melting Slicks
Joined: Mar 2001
Posts: 2,671
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From: New Jersey
Someone else just had this issue, turns out the electric radiator fan motor was intermittent.
https://www.corvetteforum.com/forums...post1596087379
https://www.corvetteforum.com/forums...post1596087379
Last edited by ersatz928; Jan 1, 2018 at 06:30 PM.
Racer
Joined: May 2014
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please let me know if you find a fix! i have a 2014 model and my daily work commute is as you have described so it has happened about 8 times. this only started happening the past year or so. Took it to the dealer 5 times but they never fixed anything because they could never find anything wrong. Contacted GM but never got anything back :/
Btw, the temporary fix is to turn off the car and turn it back on, it will turn the fans back on and lower the temp.
Btw, the temporary fix is to turn off the car and turn it back on, it will turn the fans back on and lower the temp.
Last edited by Greenkirby21; Jan 3, 2018 at 11:16 AM.
Moderator emeritus
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From: Jacksonville Florida BWO Dayton, Cincinnati, Bloomsbury NJ, Cincinnati
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Well, I agree on the temporary fix. Problem is, I can't drive the damn thing to the dealer with the temp in the red, well, I guess I could but I'm not sure if the engine would like that.
Racer
Joined: May 2014
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totally agree, and i keep using the argument with the dealership. whenever it does happen, we are talking about seconds or a minute or so before it reaches red - no time to make it to the dealership at all. i took a video of it when it did happen, show the fan is off, but nothing came out of it. They had my car for about a week trying to replicate it but couldn’t and sent me home
Le Mans Master
Joined: May 2000
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From: Redmond WA
Wouldn't having the AC on force once of the fans on and solve it ir at least reduce it? I don't understand why having the AC on doesn't change it???
Last edited by davepl; Jan 3, 2018 at 11:46 AM.
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Elmer
Melting Slicks
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From: New Jersey
There are no fan relays. The PCM sends a control signal to the fan control module, which then applies 12V variable power (PWM) to the fan motor. The fan control module is mounted next to the radiator fan, on the fan shroud. The PCM sends the PWM fan speed signal based on the engine temperature as sensed by the Engine Coolant Temperature sensor. The fan control module is fed +12V thru an 80 amp fuse located in the aux fuse box.
Last edited by ersatz928; Jan 3, 2018 at 10:25 PM.
8th Gear
Joined: Feb 2017
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Overheated again
I just got my car back from the dealer today after they could not find an issue. It only overheats on long trips and when i get stuck on I35 in stop and go traffic. Two weeks ago it did it twice on the weekend. One day was 75 out and the other it was 83. Message on DIC states Engine overheating and something about Engine at Idle. Could not pull off highway on the first occurrence due to construction and barricades on both sides. once i got up to speed the temps went below 220 and stayed there. I have had my 2014 z51 m7 for about 15 months an this is the 3rd time it has overheated on me. I can't really check fans when im stuck in traffic but i will try the restart if it occurs this Easter weekend trip down I35.
Cruising
Joined: May 2014
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I had the same problem, went to the dealer twice with video, pictures etc, dealer could not duplicate. It only happened when the vehicle was stopped or moving very slowly, once I started moving and got up to about 40-50 mph, temp dropped back down under 220. Recently I installed the 600w performance cooling fan and a new 160 degree mishimoto thermostat, so far no more issues, but waiting for hot texas summer.
Instructor
Joined: Jun 2013
Posts: 132
Likes: 1
From: Lafayette LA
I have had same issue. I have a 2014 Z51 and was coming home from the Bash at the museum on Sunday. Made two stops for gas and lunch. Got 3 miles from my exit and hit construction traffic, stop and go, turned off A/C to try and assist cooling by running heater, no help. Pulled over to parking lot, was starting to lose oil pressure, cut off car, opened the hood, fan not running. Tried to restart, acted like a low battery, difficult to turn over. Let the car sit for a while, engine started with a check engine light. Fan still did not come on until I turned on A/C again. Car drove home ok.
Next morning, on Monday, I drive car to dealer, no check engine light. Dealer calls me today for more info because.............you guessed it, failure to replicate.
Has happened to me at least two other times. Once I had a Master GM Tech connect a device to the car and sent command to the fan to run at 100% and fan responded, so we know that the does run when commanded, Just have to find out why the car is not telling the fan to run.
Next morning, on Monday, I drive car to dealer, no check engine light. Dealer calls me today for more info because.............you guessed it, failure to replicate.
Has happened to me at least two other times. Once I had a Master GM Tech connect a device to the car and sent command to the fan to run at 100% and fan responded, so we know that the does run when commanded, Just have to find out why the car is not telling the fan to run.