carllangford

BlankI'm having trouble with the accuracy of the speedometer. I have a
portable GPS that indicates that at speeds above 55mph the Maxima's begins
to error. At 55mph the GPS reads 55. At 85mph the GPS shows 80. I have a
2004 Quest and the GPS tracks the van's speedo all the way through 80 (and
beyond).

I do have the occasional problem where the speedo quits working. I found
posts that pointed to the speed sensor just by the oil filter. It seems to
work its way loose and a small tap on it with a floor jack handle reseats it
and it begins working again.

At this point I'm suspecting the speed sensor. Anyone else had issues like
this? I've also seen this on a 1994 Pathfinder (automatic), though the
speedo never quit.

thanks.......

as

I had the same discrepancy in my 94 Max, but reflashed the GPS and both
of them agreed.

e meyer

Check that the tires are the same size as the ones that came on the car. If
the cir***ference of the tires is different than what the car was intended
to use, error is introduced in the speedometer (and odometer).


On 11/9/06 8:17 PM, in article
2jR4h.4644$L6.4057@newsread3.news.pas.earthlink.ne t, "AS" <donot@spame.com>

cgl

The tires are and always have been factory size. Again, at speeds above
55MPH the maxima's speedo begins to drift away from the speed indicated by
the GPS. The GPS has the latest firmware and does match the speed indicated
in the Quest.

e meyer

Its possible that the speedometer reads high by design. I recently timed my
'96 I30 and my '91 240sx with the cruise set at 70 MPH and a stopwatch
through 5 miles of mile markers on the interstate. The speedometers on both
read fast compared to the time it took to travel 5 miles. The i30 was off
by 3 mph & the 240sx by 5. We then put new tires on the 240sx, using a size
that was an original equipment option on that car (its the next bigger size
from the standard OEM tires) and repeated the experiment. It now reads 3
mph fast at 70mph on the same stretch. I conclude from this small sample of
3 Nissans from that time period that error was intentionally built into the
speedometers.