Coolant level is ok with me (just did coolant flush, no air bubbles either), I'm just wondering why the heating system isn't sufficient enough to even keep the windows clear of ice buildup when driving. Could it be a simple thermostat change? Anyone know? I don't want to spend the $ on a new thermostat if it's just a design flaw?

I expect hot air after 30 mins of either city/highway driving, all my previous cars at least doesn't have problems keeping the front window from freezing when I'm driving. This is with my fan set to HIGH directed to the front windshield only am I only able to achieve 70% of my windshield from freezing.

 

Mine takes about 4-6 minutes after starting when the engine is cold before the heat comes on. I'm glad the fan doesn't start b;owing until warm air is available! Mine gets hot enough when set at 70 usually. Sometimes I have to turn it down to 68 and sometimes up to 72. When set on higher temperatures it gets too warm. Be sure it is on Auto so that air is heated and directed correctly. When put on Defrost, the A/C comes on to take the moisture out of the air and the stuff hitting the windshield might not be super hot.

MY heated seat gets quite hot on High and after about 8-10 minutes I have to set it on the lower setting. If your butt isn't burning, something is wrong (not with your butt!). I had a Saab once where it took me 1 or 2 years to realize that the heated seat didn't work because it was unplugged under the seat. Check things like that, including the fuse. But if it is under warranty, let the dealer check.

 

everytime i put on defrost, the a/c comes on and I set the temp high and turn off the a/c and keep defroster on. Wouldnt the a/c on with defroster make it colder? I thought a/c is for keeping you cold and cool. Why does that come on when you press defroster? I always turn it off.

 

The ac comes on with the defroster to keep the inside of the windows from fogging up. The ac removes any moisture that's in the air. If your windows ever fog up just put on the ac and see how fast they will clear up.

 

^^^^ hm... mine is auto and i dont have the oil gauge =\

dont get me wrong, my heat works fine, its just other cars heaters are much more powerfull

 

I've been amazed at how fast my '05 heats up. Within 3 miles of departing the garage, it's blowing warm air. I keep mine on auto mode. Depending on the difference between the interior and the outside air temp seems to me to determine how high the blower speed kicks in, once coolant temp is high enough.
As for the heated seats; on high setting, I notice heat within about 5 minutes. Once I feel heat, I turn the seat warmer off as I don't really like the hot butt sensation.

 

I usualy will put it my 5at in manual mode, and keep it in 2-3 until it starts to blow heat.

If you switch the heater to manual mode and put it on full blast when the car isn't up to temp, your vehicle will heat up a lot slower

 

The A/C is supposed to come on when you put on "Defrost" because it is really trying to defog the air that goes to the windshield by taking the moisture out of it. I believe the A/C does not kick in if the temperature is below some fairly cold number, because then it wouldn't work right. But the air that comes out when it is on defrost is not particularly cold, if I recall from the last time I put my hand up there.

If someone has the shop manual, they can tell you what the air temp from the heater should be and you can check it if you can get a thermometer into the vent. You can't get an accurate reading by putting the thermomneter outside the vent. But if it is still in warranty, have the dealer check it and ask them to do the temperature check.

 

i have a 03 sedan and i have the same problem...i've had many vehicles before but g35's heating is very slow and velocity is very poor at max.

 

You raised a good point here - It is very difficult to get coolant back in to the G if it is completely drained. It will not be properly filled on the first try. Check that the radiator is full (Don't check when hot) and check the reservoir to make sure it is at MAX when hot. The symptoms you describe are exactly what happens with in insufficient coolant.

I find that my G clears the windows faster than any car I have ever had, so it is not a design problem. The drying feature of the A/C unit is awesome.

 

Just checked my car, rad fluid level is fine, this is on a cold car.