Jerry wrote:

> I am getting 41-43 MPG highway and 35-37 MPG city (summer) - 2002 SL
> 5-sp. BTW, believe it or not, I started getting better MPG (1-2 miles)
> after I disabled DRL about a year ago.

The highbeam lamps are running in series when in a 'DRL' state, meaning
that each uses about half of the electricty normally used to power the
lamps. How could this possibly affect the MPG? Do the DRLs really put
that big of a strain on the alternator? If it really does, then it
seems logical to disable all "extraneous" electrical equipment - radio,
instrument panel, etc.

I would tend toward saying that 1-2MPG difference could be attributed to
a whole host of factors including slight average temperature
differences, tire pressure, road conditions, different fuel mixtures
from the oil companies, slightly different if imperceptible driving
habits, etc. Without proper experimental control conditions, it really
is nearly impossible to account for that slight of a change. It would
be VERY interesting to measure alternator output (amps, volts) and
engine output (RPMS) in a garage setting with and without: the DRLs,
normal headlights, high beams. While not conclusive, I think it would
be enlightening.

Secondly, disabling the DRLs, while your choice, is also defeating a
safety feature of the vehicle. We don't turn on our headlights in the
rain (the law in most states) because it helps us see better - but
because it helps others see us better. Before DRLs were popularized, a
study in Europe found that you were some 30% less likely to be in an
accident with your headlights on - simply because of the added
visibility and how our brains react when we see light rushing toward us.
Since I read that, I always turn on my headlights in vehicles not
equipped with DRLs; and turn on the parking lights on my DRL-equipped
saturn so that I'm (slightly) more visible from behind as well.

-rj
98SL2