Quick fuel saving tip for Winter

[RH77]

Originally Posted by MazdaMatt

Skinny fingers were not intended to grip -35 steering wheels.

That's what gets me first -- hands/fingers. Then core temp goes and rest is downhill.

Although, I'd take the cold over the heat.

I once rented a Buick with a heated steering wheel. That was nice. Too bad it was a guzzling V-8.

Anyhoo, earlier-on, we were talking about underhood insulation. Is that similar to what's on my Dad's 1988 Oldsmobile or something more custom. I haven't seen a car with insulation (that I can recall) for a while.

RH77

[Will]

I think the hood insulation may have been for engine noise as much as anything else. It seems to have been on luxury cars longer than it was on others. My 93 Century had it.

[mavinwy]

Actually, it is not just luxury cars. The Neon has it installed, but I agree it is probably for noise restriction rather than for heat retention. Most manyfacturers want to get all of the heat OUT of the engine compartment. It makes cooling easier and prolongs engine life if a constant temp can be maintained.

In fact the battery on the neon has a "themoguard" with a cold air tube. So they had to add additional cooling....

Jim

[whokilledthejams]

@ Mr. Mullet:

Good tip. I disabled the AC-on-with-defrost in the xB, and the Impreza I previously had. It wasn't a huge waste of fuel, but every bit counts. I disabled them semi-permanently by taking apart the HVAC controls in both cars, and simply moving the tiny switch that is closed when the defrost setting is selected. Sort of a pain to do, but I get results.

[mwpiper]

There is a difference between defrost and defog. Defog works better with A/C (dryer air and all that). Defroster works better without A/C (melting ice with cold air is so effective). The air conditioner gets cold way faster than the engine gets hot.

If it was just an issue of the first few minutes of driving, I wouldn't be as concerned. But my Escape is very prone to fogging up when it rains, more so than any other car I've owned. That means that if I drive in the rain, I have to constantly turn on the A/C to defog. A steady draft across the windshield would do the same, but I don't have the option. Hence, I see a switch in my future.

Likewise, I suspect that the heater core is always hot because when I turn on the vent, the air is warmer than ambient. I can find no indication of a heater flow cutoff valve. Turning off the heat will require a valve, motor and switch, a little more involved than the A/C switch.

[dentprone]

Originally Posted by mwpiper

Likewise, I suspect that the heater core is always hot because when I turn on the vent, the air is warmer than ambient. I can find no indication of a heater flow cutoff valve. Turning off the heat will require a valve, motor and switch, a little more involved than the A/C switch.

+1 on the defog/defrost

I worked on a late model F-series that was like that. I think it is fairly common nowadays. They use a door to open/shut off the heater core to/from the rest of the box. Unfortunately, when the door motor goes bad, it is in a real fun place to get to.

[Formula413]

I hate HVAC controls that don't allow you to select compressor or recirculation independent of vent setting, both my cars have the dumbed down setup. But I'm pretty sure my Escort disables the compressor for the defrost settings when the ambient temperature is below a certain point, I think 45 degrees F. I assume it uses the IAT sensor to do this.