One-time overheating issue
 

I've owned my 2012 since late February, it was originally dealer inspected and zero issues since. This past week, after approx. 15 minutes of idling in a parking lot (typical) the car began to overheat a bit, it just moved up three notches from normal operating temp. Coolant was fine, I went in to work and drove home later no problem.

Took it to the dealership today. No leaks, fan is working, thermostat is working, they had it for about 8 hours and could not get it past normal temp. They flushed the coolant in the possibility of an air pocket, which was fine since I was going to do that this winter anyway but I don't know how an air bubble would form out of nowhere.

I do notice this car reaches operating temp. really fast compared to anything I've owned; as in, I close the garage door and am barely down the street and it's already at normal..... but I figured it was just a Z thing and it never overheated so I never gave it attention.

Anyone have any insight on this? I've been driving it hard and can't get it to overheat again. I'm in central TX and that day I believe it was about 107 with the heat index, but that's every day here... of course the oil temp is in the 220-240 range constantly but I never had a problem with the water temp.

Not sure if my car has an aftermarket oil cooler on it, (bought it used its a 2012) but I'm from Houston so it is really hot here as well but my car has never gone past 220 even when I'm driving pretty hard on the highway. Weird.

Not weird at all. Idling cars have a tendency to overheat, because of the lack of air flow.

As per wanker, it's probably normal. The 370Z runs hot to start with and it gets worse when idling.

The dash water temp gauge is VERY non-linear. Buy a OBD/CAN tool to see what water temp is doing.

Just curious, but do you ever have the cooling system flushed or do you just do drain and fill?

Flushed. Though I hadn't done anything coolant related to this car yet.

The gauge did always seem really non-linear to me but I hadn't really given it much thought, I've idled it for over an hour at times and didn't have any issues but I guess once it's 100+ outside it's a different story.

So you've never had the cooling system serviced while you've owned the car?

No, it was serviced at the dealership via previous owner about 12k ago.

Check the radiator fans if it happens again.... or maybe a sticky thermostat that didn't open properly.