I was sitting in traffic jam a couple weeks ago, when my AC suddenly changed over to vent…I checked my dash & noticed my thermostat was almost to the top line…Have never had this happen though I know your car can overheat when you run the AC at a standstill. So I turned off the AC and the thermostat worked its way down into the normal range. Didn’t think too much more about it, until it started repeatedly doing that this week while I was driving. I just turned the AC off and ran the vent. Then this am, the thermometer started going up again, even with both the AC and vent off…Anyone know what this means? It started doing this right as I was pulling into my parking spot, so I am wondering if it is even safe to drive to the mechanic on Monday or whether I need to have it towed.

Also, is there anything I need to check to make sure a fluid level is OK or anything like that? I get all the regular maintenance done, so I am hoping that when they say they’re checking all the fluid levels they’re actually doing it, but who knows.

Forgot to mention the vitals: 2003 Nissan Xterra, 4L, 2WD, about 90K miles, haven’t noticed any other change while driving, except the thermostat issue…still getting great gas mileage, no major issues with the car (to date…)

sorry to ask the obvious but is the radiator fan working…

Thats OK - not so obvious to me since I’m just starting to learn about cars. So I just ran out & popped the hood - if the radiatior fan is the big white fan right behind the grill & right under where the radiatior cap is, then yes, it’s still working. But I just checked the coolant and it’s almost empty. So much for them topping off the fluids at each maint. I guess. I would think the first step would be to refill that & then if that doesn’t fix it then go looking for actual mechanical problems?

make sure you burp the system to avoid air pockets…someone I am sure will follow up and tell you the safe and sure way to do that.

… And watch it. Even if you don’t see a leak, if you have a head gasket problem (or some other problems, you could look coolant fast.

Blaming “them” when your fluids get low is, lets just say weak. It is your job.