Want High MPG Plus Power and Performance?



Diesel-powered
cars could be the ticket — as far as giving us very
high-mileage cars (50-plus MPGs) with excellent power/performance
and without the liabilities of hybrids — including the additional
expense/complexity of having two powerplants (a gas engine
and an electric motor) in the same vehicle — or the compromised
economy/performance of hybrids at highway speeds.

But, as my
week in the just-launched 2014 Chevy Cruze diesel made all-too-plain,
the government is making it very hard to make a case for diesel-powered
cars.

I’ll
explain.

The Cruze I
test drove (read the review here)
comes with two features that many potential buyers may not like.
Unfortunately, they are not optional. If you buy the car,
you’re stuck with them — just like Claymores in the
dashboard (air bags), always-on headlights (Daytime Running Lamps)
and other such things force-fed to the American car buyer.

The first of
these features is a particulate (soot) trap built into the exhaust
system. It must be periodically “regenerated.” Very
high heat (from driving the car) is used to burn off accumulated
soot, thereby preventing it from pouring out of the tailpipe. This
is the chief reason why modern diesel cars don’t smoke —
unlike the diesel-powered infamies of the past. This is wonderful.
Except for one thing. If you don’t drive the car long
enough or fast enough (20-30 minutes continuously at speeds
of 30 MPH or more) the “regeneration” cycle won’t
work as designed. The accumulated soot isn’t burned
off. Instead, it builds up inside the system. Which makes the system
unhappy. And that makes the car’s computer — which controls
everything — unhappy. In turn, you will soon be unhappy.
Because the car’s computer will flash a “trouble code”
(a dashboard warning light will appear) and it will then limit how
fast the car can be driven — until you take it in to Mr. Goodwrench
to get that Great GM Feeling.

If you do a
lot of highway driving, you may never have this problem. But people
who only use the car to commute, who do mostly stop-and-go driving,
may be in for an unwelcome surprise. I wrote a column a few weeks
ago (see here)
about the DC ambulance that went kaput by the side of the
road — with a dying patient inside — as a result of
the vehicle’s computer getting pissy because the “regeneration”
cycle never had a chance to do its thing — the ambulance being
used infrequently and mostly driven for short distances at lower
speeds. That was a Ford. Be advised the “regeneration”
thing is by no means just a GM thing. It is becoming a
universal thing — because it is the only thing that keeps
particulate emissions in line with what the EPA demands. You can
agree or not that curbing soot to nil is a good thing. The question
is whether it’s smart to be so strict if the only way to do
it is to make diesel-powered cars vulnerable to random unplanned
pit stops. Because buyers aren’t going to like that. And once
word gets out, they may not buy diesel-powered cars. Which kind
of makes the whole exercise pointless. Unless the point of the exercise
is to strangle diesel-powered cars in the crib, before they get
a chance to win hearts and minds — and achieve widespread
consumer acceptance.

The next diesel
“feature” is potentially much more of a consumer turn-off:
Urea injection.

You’ve
no doubt heard about catalytic converters. All gas-powered
cars have these devices. They catalytically (chemically) convert
exhaust gasses from obnoxious and harmful to not-obnoxious and harmless
— which is why the better part of any modern car’s exhaust
stream (upwards of 95 percent) is composed of water vapor and carbon
dioxide, both compounds having no ill effect on the quality of the
air we breathe. Well, urea injection in diesel engines works on
a similar principle. By spraying a shot of urea – basically, horse
pee — into the hot exhaust stream, the exhaust gas is chemically
changed to more benign compounds. But unlike the gas-engined car’s
catalytic converter — which requires no periodic maintenance
— a diesel-powered car’s urea injection system requires
regular topping-off of the urea tank. In the Cruze, there’s
a filler neck in the trunk. The tank holds about five gallons of
the stuff — which is typical.

So, what’s
the problem?

Read
the rest of the article

July
5, 2013

Eric Peters
[send him mail] is an
automotive columnist and author of
Automotive
Atrocities and Road Hogs
(2011). Visit his
website
.

Copyright
© 2013 Eric Peters

The
Best of Eric Peters

Republished with permission from: Lew Rockwell