The Automatic Climate Control system. When set to auto, i hear a fan that continously runs all the time! Is that the Air conditioner? If so, then using the auto mode will reduce fuel economy right? Should i just use Econ mode for heating the car up?

Can someone explain Overdrive to me? I thought that driving with the O/D Off light when driving less than 45mph, was normal? How does this work?



Thanks guys!

 

the a/c fan is on because the freon is being cycled around. the freon needs to be cooled before it is going to be recycled back into the compressor.. i forgot how it all works agian tho. but you have two fans. one is when your car is moving real slow so not much airflow is going through the radiator so the fan kicks in to generate airflow. the ac fan is always on whenthe ac is on. the ac can decrease fuel economy since it robs some power from the engine. it's driven by a belt and when it's on it'll create tension. but it's all good.
i drive with the oD on all the time.

 

The A/C-heater when operating in the AUTO mode is controlled by a microprocessor and a LAN controling the A/C, heater, and several air flow doors.

Quick explination (take from the Nissan ESM):

AUTO SWITCH
The compressor, intake doors, air mix door, outlet doors, and blower speed are automatically controlled so that the in-vehicle temperature will reach, and be maintained at the temperature selected by the operator.

ECON SWITCH
By pressing the ECON switch, the display should indicate ECON and the compressor always turns OFF. With the compressor OFF, the system will not remove heat (cool) or de-humidify. The system will maintain the in-vehicle temperature at the set temperature when the set temperature is above the ambient (outside) temperature. The system will set the intake doors to the outside position.


In simple terms:
AUTO every thing controlled by microprocessor to maintain constant temperature.

ECON only the heater will work if needed to raise the temperature. In winter (for cold climate owners), this is the best setting to use

 

does driving in Auto mode increase fuel consumption? Since the A/C is on all the time, it is definately consuming power from the motor, and should increase fuel consumption and lower performance! The manual does not mention this!

The reason why I asked this is because I was doing a test drive on the highway today, and noticed this car has horrible fuel economy. To make my test conclusive, I will conduct the same trip again tomorrow morning, and average the results (my max speed was 75mph with the cruise control doing most of the work).

This car had me so worried that I decided not to go to the last exit on the NJ Turnpike, and immediately stopped for fuel!

The car now has 300 miles on it, should I wait until the recommended 1000 miles before making my final judgement? It's just odd that my brothers Nissan Pathfinder could drive the entire Turnpike on a full tank, and have a half tank at the end of the highway, while my brand new Maxima fuel needle is reading close to E!