Hey guys total newbie here, just got my white 2004 HCH last week (and LOVING it so far!). Sorry if this has been asked and answered already.

I'm wondering if the current MPG indicator is reflective of the MPG you are getting while using the A/C or is it simply based on the physics of your driving (speed, acceleration, etc.)

Sorry if this is a dumb question but it will have a huge impact on whether I am primarily using A/C or the ECON button.

Please ONLY answer if you know for certain one way or the other, as if no one does, I will just call my local Honda dealer. Figured I'd try here first cause if there's one thing I have found out it's that more often than not we know more here on the forum than some of those "advisors" you get on the phone at dealerships!

Thanks in advance!

 

Wow, nobody knows this??

 

The MPG indication is a result of measuring the amount of fuel delivered by the injector with distance traveled. Whether or not you use the AC makes no difference to that equasion. For example if someone is a lead foot, using the AC a lot etc it will require more fuel to be delived, reflecting a lower MPG calcuation for the same distance traveled. If someone's 10 mile trip to the store is all downhill it will require less fuel to be delivered for the distance and so a higher MPG will be calculated.

If you want to maximize your MPG while using the AC follow these guidelines:

* Do not have the compressor on while accelerating or climbing hills. The compressor can switch on anytime the "AC" button is lit.
* Do have the compressor on while decellerating or decending hills.
* If you feel the engine is under load and shutting off the AC will relieve some of that load then do so.
* Setting the climate control for a warmer car won't save fuel. It simply mixes cold air from the AC unit with the heat from the engine collant into the cabin. The air conditioner evaporator maintains the same temperature, just above freezing regardless where the temperature **** is set so there is no fuel savings.

Switching the AC compressor on/off is a bit more work, and your vehicle won't be a rolling refrigerator. But rolling refrigerators are wasteful, IMO.

Notes about defrost mode:

* Don't do any of this if you feel it might compromise safety.

Anytime the direction **** is set to DEFROST and the fan is ON, the compressor is cycling on/off regardless of the AC button light.

Therefore it is often wasteful to simply keep the controls in that position. An alternative is to keep the direction **** set to DEFROST and the fan set to OFF. If your window begins to fog up then switch the fan ON to one of the higher speeds for a minute or so to clear the windows then turn it off. The dry air passively going through the AC unit will continue to blow across the window(s) and drying the air for another minute or so.

Again, if at all possible do not use defrost while accelerating, climbing hills etc. If you are decellerating for a longer distance or going down a steeper hill then switch the fan to ON even if the windows are clear. That will help to keep the interior air dehumidified, thus keeping your windows clear.

Above all be safe.

The ECON button enables/disables the engine auto-stop while stopped. That's all it does.