IIRC a FEW '14s had a recall due to a faulty surge tank cap issue.

I don't know if this is the issue, or not, but the cars affected had a slightly out of round male portion of the cap assembly that blew when under pressure.

 

I also have been having the same issue with my 2014 Vert Z51 Auto. I had the same experience with the dealer in S FL around NO CODES, etc. Today I brought it in for a new battery and the service rep told me a number of vettes had come in with the same issue and there is now some TSB? That addresses this and the fix is to change the water pump to the newer version in later years of the C7. Going to have that done, but does this ring a bell with anyone?

 

My 2014 overheated recently during normal driving and temps. Issue was a faulty surge tank cap.

 

Thanks for letting us know what it was. Could be very helpful to someone else down the road.

Glad it was easily and quickly fixed. And you are back motoring!

 

I have a 2014 c7 corvette, 26,000 miles. 4 months ago I noticed coolest pouring out of the over flow to the coolest tank. Took it to the dealer, after doing a pressure test, they replaced the radiator. 2 months later the vett over heated. Took it to the dealer. They replaced the water pump. Now, after driving the vett about 65 miles, I pulled in my driveway I noticed a trail of coolant leading to my vett. I let the vett set for a while, when I removed the coolest cap, the tank was almost empty. The weather was about 103* today, but I don’t believe this would cause the coolest pour out of the overflow.
Anyone have the same problem?

 

Mine was a faulty surge tank cap. It’s an inexpensive part that can cause big problems.

 

My 2015 Z51 A8 has a similar problem. After a long trip on the interstate, the ECM fan control seems to go to sleep. I have no problem while on the interstate, but when I exit the interstate and enter stop and go traffic, the car begins to overheat. It doesn't matter what performance mode the car is in and I wasn't driving "spiritedly." There is no front license plate obstruction and the radiator/condenser is clean. To correct the problem, I have to turn the engine off and restart. The fans come on and the engine temp returns to normal, even while sitting in stop and go congestion. What is going on here? This has happend to me now 4 times in the past 3 years, each time after being on the interstate for 4+ hours. The car now has 14,500 miles on the odometer so it is truly the definition of an intermediate problem. I can't reproduce the problem for the dealer. They want to drive the car around the block and tell me they "can't reproduce the problem." The problem only seems to occur after long interstate trips of 4+ hours but doesn't always happen. I've made the trip several times without issue. I'm convinced it's an electrical problem but don't know how to fix it. My guess would be the ECM but without a code, I'll never get GM to replace it. This is very frustrating. Has anyone else had this problem and know the fix?

 

My 2015 Z51 8SP has a peculiar problem. After a long trip on the interstate, the fan control seems to go to sleep. I have no problem while on the interstate, but when I exit and enter stop and go traffic, the car begins to overheat. There is no front license plate obstruction and the radiator/condenser is pretty clean. To correct the problem, I have to turn the engine off and restart. The fans come on and the engine temp returns to normal. What is going on here? This has happend to me now 4 times, each time after being on the interstate for 4+ hours. I can't reproduce the problem for the dealer. They want to drive the car around the block and tell me they "can't reproduce the problem." This is very frustrating. Has anyone else had this problem and know the fix?

I wonder if it could be a failing fan thermostat switch.

 

Welcome to our forum Hudsong. I suggest you document the problem with a cell phone video and then take that to your dealer.

 

Can't rule anything out at this point. The problem is very intermittent and is always occurs after a long interstate run. If the thermostat switch was failing, I think I would see the problem more regularly though.

 

That's a great idea jsvette. Will do. Somehow, i'm not that hopeful the dealer will accept that as reproducible. If the car throws a code, the dealer will take action. Without the code, they just hand the keys back and shrug their shoulders.
Anyway, video proof is the next best option to plead my case. It would be helpful if there were enough cases of this issue to reference. Most overheating issues I've read about involve tracking or spirited driving on a hot day. My issue has nothing to do with that unless 80mph on the interstate in 80 degree weather is considered aggressive driving.

 

Hi there, 15 Stingray, no frt plate, automatic, 4500 miles.
Had the same problem once, message center alerted me to shutdown engine - overheating. I then had a similar occurrence but that time without the boiling over. Both times it happened had been after approximately 100 miles and getting stuck in traffic. As soon as I got air flow cruising at 50 + MPH temp came down. This is a typical cooling fan not engaging problem. Dealerships were no help. The first time they replaced water pump and thermostat. I don't believe they will or can take the time to recreate the problem. Vette overheated again after that repair. Same dynamics but caught it before boiling over. I'm more aware and have a problem if my baby overheats. The dealer kept telling me that vettes run 230 -250' - B*llsh*t. 195' almost always. This second time I was able to keep fresh air flowing all the way to the dealership, pulled up and let it run so I could show the writer that the temp was climbing again. Same stupid answer that they run at 230-250' . Afterwards I realized that they weren't going to even acknowledge I had a problem. Once the vehicle restarts it seems the electronics resets and it will be fine for a while. But this inhibits long wonderful jaunts through any kind of road tripping.
My solution was to put a different cooling fan assembly on. The original fan assembly is a 500 watt unit. It is self contained meaning the electronics are part of the whole assy. It is controlled by the PCM on what is called a pulse width modulated signal. While it is possible that the connector , wiring or PCM is at fault, the most likely I felt was the assembly. I had previously checked the connector. GM has a 600 watt unit available and since I thought the cooling fan electronics were intermittently bad, the thought of a more powerful fan had been appealing ever since I'd read about it. It is now installed, Not a long repair and pretty easily accomplished. Vette runs at 195'(isn't that amazing?), I feel more confident on long trips but still watch my gauges. Will post updates from time to time

 

BTW the coolant temp sensor is the signal generator for the PCM to control the fan circuit. Thanks for your post, I believe our descriptions match. I feel better knowing I'm not the only one experiencing the same problem with the Vette and that the dealership doesn't or won't try to duplicate it. I actually wanted them to get in touch with GM engineers. Oh well Thanks Hudsong

 

I have a 2014 vert automatic, it has 25k on it and it has overheated twice. Both times were in stop and go traffic on a warm day but not hot. I had it towed to the dealer both times, 1st time they had no idea and sent the car home. The 2nd time I noticed the fan was not spinning when the car was hot and told the dealer they once again could not reproduce the problem but replaced the water pump on my car. I asked why wasn’t the fan spinning and they said it should of been spinning but no idea why it was not.

 

I had an overheating problem with my 2014. Dealer could not duplicate. There is a service bulletin (PIP5176) that says if concern could not be isolated, replace the coolant manifold assembly.

 

Welcome to our forum tjo and thank you for bringing up the TSB PIP5176. This does not fall under a recall, however, the related information is:

Overheating issue due to pump flow per bulletin PIP-5176.
Engine coolant manifold replacement
1 - 12676472 B-(S) Pump
2 - 12346290 Coolant
1 - 22768503 F-(S)Hose
Faulty coolant manifold. Follow service procedure outlined in Doc ID#3704942 replace coolant manifold assembly.

 

Original owner of a 2014 LT2 non-Z51 with the 7-speed manual with 60k miles. I've had this issue happen to me about 5 times now. The first time was after a highway drive across town then came to a stop in stop-n-go traffic. I live in Florida so it's hot. Temp was normal until we stopped moving and rapidly climbed to 260 (luckily caught it before steam happened). Shut down the AC and set heat to max and it kept climbing. The fan NEVER turned on. My lady friend suggested I reboot the car since we're both IT and joking about it but I decided to try. As soon as the car turned back on the fan started up finally and cooled down. During these situations I also use the multi temp readout in the performance area when the car is in Touring or Eco (GM WTF why isn't this page there when in Sport or Track...) I can see all of the temps rising and the info read outs aren't glitching or jumping so whatever sensor they pull from I think is fine.

Took the car in the next day and they did the TSB PIP5176 work and inspected other things. Things seemed fine for a while but then it started happening again. Long highway drive and then come to a stop-n-go traffic situation when we arrive where we're going. I typically have the car in eco mode during the long highway drive. Every time the fan fails to start when the heat jumps up. Dealership per the usual cannot reproduce the issue and also don't seem to care even after bringing up the lack of fan starting every time. "Rebooting" the car seems to resolve the fan not starting issue. So my guess after reading this thread is either the fan plug issue Swiss mentioned or some part of the fan assembly like KaianC7 mentioned or the fan thermostat switch Mobius mentioned. It could also be some of the absolutely horrendous programming and lack of intercommunication between modules the 2014 has... (Don't get me started on the 2 year long debug process I went on to figure out why my car alarm went off every summer in the heat. Spoilers, the dealership was also useless in this process.)

So then to resolve this I'm going to look into the following;

1. Inspect the fan plug, look it over and give it a good shaking and cleaning
2. So what part exactly is the fan thermostat switch for our cars?
3. What fan assembly did you buy KaianC7?

 

 

Welcome to our forum brentil. Sorry to read of your issues. Hopefully one of our members will be able to provide you some information to resolve the fan switch.

 

Hi Brentil, GM makes a 600 watt hi performance fan assembly. The fan is a modular component and the fan controller is attached. The original fan assy in a C7 is a 500 watt. I originally wanted to just replace the controller but it is not available separately. I figured if I have to buy the whole assy I might as well upgrade. The price difference is not that much and my baby is worth it. I could go more into my story but it's so similar. If your moving you have air flow. That is all the fan does is move air through the radiator and condenser. The fan controller gets it's signal from the engine performance computer which makes its determinations through various sensor inputs and calculations. I checked data on a scanner and could have checked for signal at the controller but I didn't feel the need, the controller being the most likely culprit. The idiots at the dealership told me vettes run at 230' - 250'. that's bullshit. I hope not to offend but that's what that is. There is also a performance grille that allows more airflow but if the fan works then the engine stays cool when in stop and go traffic. Mine runs at 195' which is where the thermostat is set. I have not had a problem since replacement.
Scoggin Dickie Parts Center - GM part # 84486698 $268.65 Direct Replacement C7 Fan Assembly
If you need any help with installation just let me know. BTW I don't run a front license plate
Best of luck, Kaian

 

There is also a performance grille that allows more airflow but if the fan works then the engine stays cool when in stop and go traffic. Mine runs at 195' which is where the thermostat is set. I have not had a problem since replacement.
Scoggin Dickie Parts Center - GM part # 84486698 $268.65 Direct Replacement C7 Fan Assembly
If you need any help with installation just let me know. BTW I don't run a front license plate
Best of luck, Kaian

Kaian, excellent that's exactly what I wanted to know. I also don't run a front plate since it's not required in FL and I already have the higher flow Z06 grille on my car but it hasn't helped in these cases since it's always at a stand still and the fan failing to turn on. I think for under $300 replacing the fan with a newer/better one is definitely worth a shot to see if it makes this permanently go away.

How involved was the replacement of the fan assembly?

 

I found the installation guide for it online. It says to "Remove radiator return hose retainers (2) from the back of the Fan assembly" but it never states you have to drain the coolant first or refill afterwards. Can you really remove that line without draining the system?