Winter complaints

[virtual]

It's too early to tell if this was a one off, or is an early sign of an ongoing problem, but I was really surprised yesterday morning when my rear passenger windows were fogged up. The defrost settings did a fine job of clearing up the front and rear windows, but as I was trying to merge on a big road the angle I was at had me looking through the rear passenger window to see the road I was trying to merge with and I couldn't see much because of the fogging. I had to lower the rear window to be able to see well enough! Eventually it cleared up, but it definitely took a while to do so, and like I said it put me in a dangerous situation in the interim.

My wife's little Mercedes has terrible problems with the front window fogging up in the winter, and then when you put it in defog mode it blows really hard and really loud until you turn it off manually. My old Explorer never had any fogging issues so I guess I'm spoiled. Hopefully this was just an isolated incident, but I'm wondering if anyone else has had any similar problems?

 

[corkey]

it's this time of year i question the validity of the cold air intake ?

seems with real cold air mileage goes out the window,,

mine went down to just over 14 mpg recently , but it's also been pretty cold out,,,

 

[RandyH2]

While I won't pretend to be an engineer, my understanding of the cold air intake is that colder is better. I don't know if the intake actually lowers the charge temperature below the range of compensation by the engine management system - but I doubt it.

My guess is that the cold weather has resulted in lower air pressure in your tires.... And perhaps more time idling/warming up the vehicle?

 

[Kpwweb]

While I won't pretend to be an engineer, my understanding of the cold air intake is that colder is better. I don't know if the intake actually lowers the charge temperature below the range of compensation by the engine management system - but I doubt it.

My guess is that the cold weather has resulted in lower air pressure in your tires.... And perhaps more time idling/warming up the vehicle?

Cold air is also denser = more of it...

More air = more fuel to maintain desired air-fuel ratio...

Engines always make more power in cold weather because of this...

Compounding the problem, so to speak, is that gasolines are reformulated for cold weather. Which usually entails less power density per gallon.

So you are using more gas because of denser air and you are using more gas due to the gas being less dense...

Plus most usually let their cars warm up more, and idle more, and less traction, and using the AC more for defrost which is more load on the engine, and ...

All that together = lower mpg

 

[RandyH2]

^ Except you should need less gas because it is more efficiently burned for the same power.

The big culprit, which I forgot, was the switch to Winter gas- that is responsible for ~10% decrease in mileage, in my experience.

 

[Chimmy76]

It's too early to tell if this was a one off, or is an early sign of an ongoing problem, but I was really surprised yesterday morning when my rear passenger windows were fogged up. The defrost settings did a fine job of clearing up the front and rear windows, but as I was trying to merge on a big road the angle I was at had me looking through the rear passenger window to see the road I was trying to merge with and I couldn't see much because of the fogging. I had to lower the rear window to be able to see well enough! Eventually it cleared up, but it definitely took a while to do so, and like I said it put me in a dangerous situation in the interim.

My wife's little Mercedes has terrible problems with the front window fogging up in the winter, and then when you put it in defog mode it blows really hard and really loud until you turn it off manually. My old Explorer never had any fogging issues so I guess I'm spoiled. Hopefully this was just an isolated incident, but I'm wondering if anyone else has had any similar problems?

Put the second row vents blowing on the windows it should fix that

 

[colintrax]

^ Except you should need less gas because it is more efficiently burned for the same power.

The big culprit, which I forgot, was the switch to Winter gas- that is responsible for ~10% decrease in mileage, in my experience.

This is debatable. You're burning more gas to idle, or at WFO, and when coasting. Burn less when accelerating. So I think it's a wash.

 

[virtual]

Put the second row vents blowing on the windows it should fix that

Excellent suggestion, thanks so much! It seems like a totally obvious thing to know about, but apart from sitting in the back seats when I was evaluating different car options I haven't been back there since, so I didn't think to check out the rear vent patterns.

 

[JFUSION]

Put the second row vents blowing on the windows it should fix that

This is what I do on my Explorer. When needed I just reach behind with my hand an turn the fan control knob on as high as I feel is needed, and I keep the vents blowing towards the windows. I do it with all four, but you can close some off and push more air towards the ones you want.