Starts off at normal operating temperature for a few miles or about 10 minutes. After that the engine temp slowly rises, especially at a dead stop or in slow traffic. I just replaced the radiator cooling fans and I tested them to make sure they turn on so that isn't the problem..
Today there was smoke coming out of my engine compartment, but I'm going to attribute that to the coolant that splashed around during the fan replacement.. Anybody have any ideas as to what could be causing my engine to overheat? Could an exhaust manifold leak have anything to do with it? Thanks in advance..

 

Try replacing the thermostat ($20) and radiator cap ($8).

 

Other than the dash temperature gauge, what indication is there that the engine has actually overheated?

Are you telling us that your temperature gauge climbs to a level that indicates a hotter than normal temperature or are you telling us that the engine has actually overheated?

If the former is true, replacement of the ECT sensor and/or temperature sending unit might be all that's needed.

Read through this thread ... https://maxima.org/forums/4th-genera...verything.html

 

Your infinitI is mostly mechandily identical to the 4th gen Maxima.

You will find many more helpful members there.
There are far more Maximas than Infiniti.

replace the rad cap.

I'm going to venture a guess. You need to replace the radiator.

they can be found on ebay as little as 40 dollars for a cheap one, 100 for one which appears to be of good quality.

 

Did you remove and test the thermostat yet?