Cooling system trouble

[lemwoh71899]

Hello Everybody, I have a 2011 Pathfinder (V6) that seems to have an issue with the engine coolant. The vehicle has overheated twice in the last 8 months and I am not sure what to do next.
The vehicle is past it's warranty so I would prefer to do what I can before taking it to anyone.
With that being said, this vehicle is leaking coolant from the reservoir after it has been warmed up. All of the coolant tubes are in good shape and I can not find any other leaks. The overheating also seems to happen when the a/c is on. The first time was when the rear a/c was turned on and this last time was with just the front. I have added coolant to the system when it is low and have burped the system but the same problem keeps happening. We have heat from the heater and a/c but my wife says that she could smell the coolant with the a/c on just before it this last overheating.
I changed the fluid last year and after is when we began having a problem. I thought that there was air in the lines after the first overheating and refilled what was low, ran the vehicle with the a/c (both front & rear) on, filled as necessary and we've had no issue until now. The vehicle ran with the a/c on, the heat on, and has been on longer trips without any issue.
That is until the other day, when my wife was with the kids and the overheating issue came back. After we are done driving there is almost always a small puddle of coolant under the front passenger side bumper (in front of the tire) and I can trace the leak from the top of the coolant reservoir. What am I missing, I've changed the coolant on more then one vehicle and never had a problem. I even changed out our camry at the same time and have had no issue. Honda's, Pontiac's, Chevy's have all gone smooth, but I must be missing something.
Any idea's?
Thanks

[atraudes]

Welcome to Nico!

I'd get the coolant leak addressed, obviously, though I don't think it's the source of your problem. It's a particularly good idea to address this first since it may be covering up a more serious leak, like from the block and could be causing low coolant levels. Is the check engine (or any similar) light on? Does it have any problems idling, starting, etc.? If something else is going on that's causing it to run rich, that could certainly explain the overheating.

Did you replace the thermostat when you flushed the coolant? If not, it's also a likely culprit and may be sticking closed at inopportune times.

The other usual suspect with overheating is corrosion causing blockage in the cooling lines, but I wouldn't suspect that on a vehicle that new.

[lemwoh71899]

The check engine light is not on. The overheating is coming form the low coolant as it only happens after enough of the coolant has left via the coolant reservoir. I have checked for the location of the leak each time and it is always from the same location, sorry for any confusion.
I'm more of less looking to find out if I am missing a step with the coolant that might not be typical. I can not find a relief valve on any of the coolant lines that help bleed/burp the system.

[Buzzman]

Sounds like you need to find the source of the leak before anything else.

[ipeelscats]

Is the tank itself cracked, or is the hose leaking? If the hose is leaking, go to a parts store and buy a new line. Bulk hose is super cheap. Take the old one with you and find one that fits. When was the last time the thermostat was changed? Have you ever had the cooling system flushed?