wales@ucla-cs.UUCP (01/07/85)
I have a 1984 Honda Accord LX Hatchback. On a recent highway trip
between Los Angeles and San Francisco, I noticed that the odometer reads
2.8% HIGH. That is, if I drive an actual distance of 35 miles (based on
highway mile markers), my odometer would incorrectly indicate that I had
driven 36 miles.
The speedometer appears to read "high" by the same amount. For example,
if I were to drive 60 mph (based on 1 minute elapsed time between mark-
ers spaced 1 mile apart), my speedometer would indicate a speed of just
under 62 mph.
Before you ask -- the tires on the car are radials of the correct size
(in fact, they are the original tires put on the car by Honda), they
were inflated to proper pressure, and the wear is virtually zero since
I have only driven about 6,000 miles so far.
I called the service department of a local Honda dealership, and was
told that inaccuracy of this type is quite common (which does not sur-
prise me) and that they can't do a thing about it.
While I am quite willing to believe that problems of this kind are wide-
spread, I would still like to fix it if possible, because:
(1) Be it vice or virtue, I am by nature a perfectionist.
(2) I would much rather have the dials and meters in my car read right
than have to waste mental energy applying correction factors in my
head all the time.
(3) For the sake of warranties, insurance, etc., I would vastly prefer
not to have the odometer indicate 10,000 miles on the car when in
fact it has been driven only 9,728 miles.
Is there ANYTHING I can do -- or have someone else do -- that can cor-
rect a speedometer/odometer rate error of this type?
--
Rich Wales
UCLA Computer Science Department
3531 Boelter Hall // Los Angeles, CA 90024 // (213) 825-5683
ARPA: wales@UCLA-LOCUS.ARPA
UUCP: ...!{cepu,ihnp4,trwspp,ucbvax}!ucla-cs!walesknutson@ut-ngp.UUCP (Jim Knutson) (01/10/85)
It's hard to make the odometer accurate over its full range so they are tuned to be accurate at certain ranges. I've also heard of setting them intentionally high a small amount to keep you under the speed limits.
ben@moncol.UUCP (Bennett Broder) (01/11/85)
I have a 1984 4dr Accord LX and have noticed the same inaccuracy you
describe. I can understand why a speedometer might be off; it is
an analog device which may have been incorrrectly calibrated. But an
odometer is simply a collection of gears which register the number of
times the front axle rotates. Since the auto maker knows the exact
size of the front tires, he should be able to mathematically calculate
the gear ratios inside the odometer.
I find it quite suspect that all '84 Honda odometers err on the high
side. This reduces Honda's warrantee liability, produces higher
revenues for its dealers (through more frequent servicings), and might
cause people to trade their cars earlier. When you multiply the 3%
error by the average life of a car by the number of vehicles Honda has
sold with this imperfection, it appears that Honda is cheating its
customers out of perhaps hundreds of thousands of dollars in lower
resale value and higher servicing costs. Is this cause for a
instituting a class action suit ??
Ben Broder
..vax135!petsd!moncol!benpgf@hou5g.UUCP (Paul Fox) (01/11/85)
a Just for interest's sake, I seem to remember that speedometers were required to be more accurate (I don't remember *how* accurate) during the same years that they were to have a maximum reading of 85, with 55 highlighted somehow. When the D.O.T. (was it them?) ruling about this was rescinded in the flurry of Reagan deregulation, the accuracy requirement was dropped too. (I believe that '84 was the first year without the req't. Is that right?) -- Paul Fox, AT&T Information Systems, Holmdel NJ. [ihnp4|vax135]!hou5g!pgf (201)834-3740
mikey@trsvax.UUCP (01/13/85)
There are specialty shops that will open up your speedo and adjust the gap (I was told they use magnetic eddy current to move the needle) to make your speedo more accurate. Don't blame the manufacturer, I was told there is a federal DOT spec that odometers and speedos are not allowed to read slow. They can be right on or fast, but never slow. I guess most companies try to play it safe with a few percent. mikey at trsvax
gino@voder.UUCP (Gino Bloch) (01/14/85)
[roll on, line-eater]
After several confusing articles, I have to point out some definitions.
ODometer: a device to measure distance travelled (the set of little
wheels with numbers on the edges, giving readouts like
00375.4)
SPEEDometer: a device to measure (instantaneous) speed (usually a
fixed disk with marks around the edge and a needle-like
readout that changes its orientation as the car speed
changes; it is read by visually noting the needle's position
with respect to the disk's edge marks)
Thus, if the odometer is off, you must correct it by changing one or more
of: the tires, the speedometer assembly (the odometer is mounted inside it),
the gears inside the speedometer, or the gears at the transmission end of the
speedometer cable. If the speedometer is inaccurate, you can diddle with
the internal spring, or you can paste a new scale over the existing one,
or you can file the magnet or the cup that it drives. If you change the
odometer gearing at the transmission end, the speedometer will also change
its calibration, so it might need adjustment - but do the gears first.
It is possible, but not necessary, that the speedometer readout is
independent of the (internal) odometer gearing.
--
Gene E. Bloch (...!nsc!voder!gino)
Extend USENET to omicron Ceti.review@drutx.UUCP (Millham) (01/14/85)
> Don't blame the manufacturer, I was told there > is a federal DOT spec that odometers and speedos are not allowed to read > slow. They can be right on or fast, but never slow. I guess most companies > try to play it safe with a few percent. > > mikey at trsvax Is this true? When my speedo reads 60, it only takes me 54 seconds to go a mile. I was stopped in Iowa for going 57 (on radar) but my speedo only read 54. The car only had 10,000 miles on it when this happened, and has the original tires. Brian Millham AT & T Information Systems Denver, Co. ...!drutx!review
ed@mtxinu.UUCP (Ed Gould) (01/16/85)
> I have a 1984 Honda Accord LX Hatchback. On a recent highway trip > between Los Angeles and San Francisco, I noticed that the odometer reads > 2.8% HIGH. That is, if I drive an actual distance of 35 miles (based on > highway mile markers), my odometer would incorrectly indicate that I had > driven 36 miles. > > The speedometer appears to read "high" by the same amount. As far as I know, the only way to change most speedometer/odometer rates is to change the gear in the transmission that drives the cable - at least that's true for mechanical ones. The reason for reading high may not be related to warranties expiring early (as Rich *doesn't* imply), but may be related to a German law that requires speedometers to read between 0% low and 5% high. In other words, the defense for speeding that goes "I was cited for going 57 but my speedometer read 54" can't be used, at least not with a legal speedometer. -- Ed Gould mt Xinu, 739 Allston Way, Berkeley, CA 94710 USA {ucbvax,decvax}!mtxinu!ed +1 415 644 0146