bpp

This reminds me that my aux heater did not function the last winter. Maybe here be the reason. Hmm.....

BarryT

The aux heater in mine turns on but it doesn't put out much heat. I'll have to get this done in a few months to see if it helps.

bpp

How do you know it turns on?

BarryT

It makes a click sound.

bpp

Well, mine's not working therefore no click. Never was aware of it (clicks) even when it worked.

BarryT

It only does it when it's really cold outside. I don't know the specific temperature.

bpp

You want to explain this one about not generating heat quickly in E85 vehicles please. Diesels yes due to efficiency, but E85? Help me.

MP4.2+6.0

Almost laughable. Lets see: they got caught using timers with the emissions controls on TDI's. Oops, a few "rogue" engineers with time on their hands. Engineers whose names cannot be uttered due to German privacy laws...and maybe a few more "rogue" executives who might be fleshed out. But no worries, lets put them on a new timer project given the skill set. Oh, the aux. heaters.

BTW, these things have been in the D3 A8's since the intro in 2004, or really mid 2003. Like 13 years ago. By at least 6-8 years ago it was obvious they were routinely burning/burnt out. Look at any D3 scan and 95% of them now code out for one or both heating elements--in ducts on both sides. On D3 board we routinely just tell folks to ignore in a VCDS scan. They cost $400 there, for EACH side. Less tongue in cheek, they maybe realized after the first 20 minutes or so heating boost function was kind of irrelevant since it pulled air through ducting from now hot heater cores anyway. And since Piech got ejected by the door hitting him on the way out--twice--which is where all the personal attention to air flow started, I guess they now decided they can clock it out after maybe 20 minutes. Also note the irony--a CEO (Piech) who can literally meddle in HVAC design about drafts that is where this technology comes from back at gestation and get press for it--to a company that today talks about a few rogue engineers and everyone on the management team still plays Schultz.

Being fair alongside the skepticism, they have clocked out outside mirror defrost for many years, and also rear window defrost. Back on my 1973 C1 there was no auto off defroster and you could literally drive around for weeks with it on--or the next cold night or morning when you saw the lines cutting through the dew but hadn't touched the switch. The switch was sloppily fit as a retro afterthought on the side of the steering column trim not visible while driving and with no dash light even showing it was on.

rdA4WtQ5

Not a chemist, E85 has a much greater cooling effect when being vaporized than E10 gas and causes the engine temp to rise much slower especially when it's cold out.

Redd

Alcohol is a "cold" flame compared to real petrol. Alcohol stoves typically put out so much less heat (and more moisture vapor) that in the 70's they were considered killers for winter campers, who needed to melt snow for their water. And couldn't do it on alcohol stoves.

Given that, and given that E10 has some 10% less fuel density than petrol, and that E85 would then have *way* less fuel density...

I could see an E85 engine running much "colder" than a petrol engine, but whether that would be real, or simply one more factor for the ECU to control with the timing and fuel feed? I wouldn't bet on. There are many factors besides the fuel type that would affect how quickly a computer-controlled engine heated up.

FWIW.