Heater and Weather Vs. MPG Questions!!!
11-09-2004, 01:46 PM
#1
Safety Car
Thread Starter
Member Since: Nov 2003
Location: San Jose CA
Posts: 4,108
Likes: 0
Received 0 Likes
on
0 Posts
Heater and Weather Vs. MPG Questions!!!
Since it's been colder, i've been using my heater more. When the heater's on, the cooling fan goes on and off every 30 seconds. Is this normal? Also, since it's been colder my average mpg went down. I was getting 14-15 in the city. Which i thought was low to begin with for an A4. Lately i've been getting 11-12. That's driving 3-4 miles per trip at about 4 trips a day. The car has 42k miles on a 96. I just did new plugs, wires, fuel filter and serpentine belt. The car is tip top. What do ya'll think?
11-09-2004, 01:53 PM
#2
Melting Slicks
Hot air is less dense than cold air, so fuel economy will suffer somewhat in colder weather. Your MPG's look pretty low though, so maybe something else is contributing.
11-09-2004, 02:16 PM
#4
Le Mans Master
Like the old days with a choke, until the car warms up (which is now taking longer) it will run rich. Being short trips will just amplify the proble. You are just getting it warmed up when you stop and it cools down.
The heater fan? Might it be the electronic controls in the auto mode??
11-09-2004, 08:53 PM
#6
Le Mans Master
The cooling fans turn on and off as the a/c compressor cycles. The compressor is cycling because the cooler temperatures are keeping the a/c pressures low. If the compressor didn't turn off, the evaporator would freeze over and you would lose the dehumidifying benefits that the a/c provides with the heat on.