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Re: Fuel economy

> From quattro-owner@swiss.ans.net Tue Aug  2 16:58:36 1994
> From: zm@mhcnet.att.com (Zafer Mehmood  [209])
> To: quattro@swiss.ans.net
> On the topic of fuel economy, if you have an automatic expect significantly
> lesser mileage than a 5 speed of the same model/year. If I'm not mistaken,
> early Audi automatics were 3 speeds (no overdrive) -> poor mileage. A manual 5
> speed Audi has better fuel economy for two reasons - less transmission
> losses and "deceleration fuel cutoff" (shuts off injectors when the car
> is in gear, clutch not pressed and throttle closed). I know for a fact that
> the CIS equipped 86-88 turbo 5000 cars have the deceleration fuel cutoff
> feature, but I'm note sure about others.

All of the new ones have fuel shutoff on deceleration also.  If you
have a trip computer, it will go to "---" because the ratio of miles
per gallon is undefined at zero consumption.

For maximum mileage (and minimum pollution), there are quite a few tips
which have been published in auto, motor, und sport magazine. In order
of potential fuel savings, the ones I have had the most success with
are (and the published average savings):

1. Do not idle engine for over 15 seconds, especially when cold = 20%

2. Upshift early using large throttle openings instead of late
   with small openings (for a given acceleration rate)          = 20%

3. Drive smoothly, anticipating lights and traffic              = 10%

As I live close to work, shutting off the engine immediately at lights
and traffic backups makes a tremendous difference.  When I let friends
drive my car who don't practice the above, it gets 18 mpg or less in
town.  On the same drive, I get 24, accelerating briskly from stops,
but keeping the revs down.  That's a 33% improvement!  My car's a
5-speed, and the trip computer is accurate.  Highway mileage at 75-80 
mph is around 27 mpg but goes down with a crosswind.

I also find that not letting the engine idle prevents any carbon
buildup.  I have never had to use the likes of Techron, and the
dealership always remarks that it seems unusually powerful for that
make and model.  Sure, the starter may not make it past 200K, but I
will have saved its cost many times over.

John Greenstreet, Senior Engineer           (jgreenst@motown.ge.com)
Martin Marietta Government Electronic Systems    Moorestown NJ 08057
WPI Class of '75, Temple Class of '94

My new car history:
1972     1975       1978      1982       1986        1989      1992
 VW  ->   VW    ->  Audi  ->  Audi  -> Mercedes -> Mercedes -> Audi
SBug   Scirocco   Fox GTI     4000S    190E 2.3    190E 2.6    100CS

POSSLQ's* new car history:
         1978       1981       1985      1988        1990      1993
       Triumph ->  Toyota ->  Toyota  ->  VW    ->   Audi   -> Audi
       Spitfire    Tercel     Corolla   Jetta GL      80       90S

*POSSLQ = Person of Opposite Sex Sharing Living Quarters
Note: All Audis and Mercedes above were sold to friends or family.