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Discussion Starter #1
okay gang...

did a few more miles today.

good news.

the odo is NOT affected. i drove about 50 miles and i reset one of the trip meter and on the gps.

they were matched. down to when the tenth of the mile turned.

so the mileage part of my original post is okay.

still the -3.5 to 3.3 MPH (revised from around -3.9) is still bothersome.

sunday, i expect to drive another 160 miles and will watch the odo for a confirmation...
 

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yeah, but they're related by time. does sube have a bad clock? :) how are speedo readings generated anyway? or better yet, how is the odo calculated? some/all cars pull a signal off the tranny. i don't get how this simple calculation could be screwed up.
 

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That's what I mean...I think the car takes an odometer reading from somewhere else. The speedometer runs off of a speed sensor monitoring a gear that is spinning in the transmission. I found that in the Tech Manual. I sure can't find anything about the odometer though.

Not sure...maybe it is the same.....
 

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CloNeGTS said:
That's what I mean...I think the car takes an odometer reading from somewhere else...I sure can't find anything about the odometer though.
ah, okay. i'll take a peek also.
 

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Discussion Starter #6
okay... i'm thinking maybe the new dash isnt calibrated correctly.

i'm sure that the sender for both odo and speedo are from one source. since everything is electrical (vs mechanical sender), there's probably a pot (potentiometer) that can adjusted.
 

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I'd kinda doubt that.....that would leave all kinds of room for odometer fraud.

Someone ask a dealer......I'm going to bet they say live with it.
 

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ADJUSTABLE SPEED LIMITER and speedo signal calibrator. Designed to be fully "programmable" the electronic part simply converts the speedo drive digital signal to a setting that is "user definable". Able to redefine the speed cut to a user chosen limit and able to re calibrate the signal to suit larger or smaller dia wheels. (Great for new big diameter wheels)

http://www.mrtrally.com.au/performance/
 

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Discussion Starter #9
CloNeGTS said:
I'd kinda doubt that.....that would leave all kinds of room for odometer fraud.

Someone ask a dealer......I'm going to bet they say live with it.
i meant for the SPEEDO...

correction, the SPEEDOMETER... not the swimsuit that fat dudes wear at the beach... :D
 

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Good to hear the ODO seems not to be affected. In that case, I could really care less about the Speedo being off- especially to the point it may save your ass when you think you are going 65 in a 55, and the cop clocks you at 62MPH and leaves you alone... :)

J/K
 

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RDiamond said:

ADJUSTABLE SPEED LIMITER and speedo signal calibrator. Designed to be fully "programmable" the electronic part simply converts the speedo drive digital signal to a setting that is "user definable". Able to redefine the speed cut to a user chosen limit and able to re calibrate the signal to suit larger or smaller dia wheels. (Great for new big diameter wheels)

http://www.mrtrally.com.au/performance/
Hmm, adjustable speed limiter? ;) Wonder if this will work with the drive-by-wire throttle. Seems what I have been reading about the speed limiting capabilities is that basically it should be easily tricked anyway... :)
 

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Discussion Starter #12
a ha! (great 1 hit wonder group from the 80's, IMO...) from the PDF shop manuals, it seems that there is a gear for the speed sensor. page IDI-10 for those who have it.

IDI-12 shows a diagram where both the speedo and odo share a common input from the speed sensor.

again, kinda-semi confirming my theory that the new speedo gauge needs a tweaking. diagram IDI00012 shows a SPEEDOMETER MOVEMENT square. but it doesnt explain what that does...
 

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I haven't checked mine, but is the speedometer off 3-4 miles across the board which would be needle-staking issue. Or is it off a percentage that affects it more at higher speeds? I work at a shop that specializes in speedometer repair and calibration and most newer cars speedos read about 2-3 miles fast right off of the showroom floor. Most state specs, if they have a spec is usually around an allowable difference of 2 mph give or take at 60 mph. So most manufacturers set them a few mph high to protect themselves from lawsuits from car owners.

George
 

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As far as I was aware, any speedometer of any vehicle can be up to 6% off, but it can only read FASTER than you are going.

So if you are actually going 60 mph, your speedometer can read anywhere between 60 and 63.6 mph.

At 100 mph, it might read as much as 106 mph, and so on.

Don't know how accurate this statement is, just sticks in my brain (no wonder I have a headache!).
 
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