Okay, here's the problem I have a 2000 Nissan Maxima, I'm on a trip to Florida from New York, It drove fine up until Florida then it started acting up getting hot and eventually overheating, I changed the thermostat and the radiator cap, the problem still continued then I took it to the mechanic and he flushed and purged it and said he checked the water pump and it was fine, I drove it around today the problem continues. There are no visible leaks no white smoke, it happens after driving above 50 for about 15-20 miles, all the fans are running, I just don't understand what the problem might be, anyone have ideas?

 

Also I forgot to mention the heater blows hot, and the a/c blows cold.

 

anyone?

 

Clogged radiator and u probably used an aftermarket thermostat which for some reason don't work on these cars

 

Just happens out of the blue?
Was the a/c on the times this happened?
At freeway speeds?

 

i would suspect headgasket or cracked cylinder, would be worth getting the system tested for a bad headgasket

 

Partially clogged radiator. Replace radiator and get OEM thermostat and you'll de fine.