Is the only option to have outside temperature guage in a 97 maxima to put on a different mirror? Does a cam lock or wedge mirror work better on a maxima? I thought that 99s came with outside temp guage, but I'm not sure. If they do, is it possible to put in a 97?

 

no, there are many aftermarket units that you can use. I had one that had 2 zones, interior and exterior. A probe goes outside the car and the other is in the unit. It has a display you can mount just about anywhere, looks like a turbo timer. It worked well for me and I had the cheepo $10 unit from wal-mart. I have seen ones that stick on the rear view mirror. But imsure the OEM mirrors with built in temp are far more accurate.

99 have a AMB button on the auto climate control, which can be added to a 98 ACC, but not any other year 4th gen.