Speedometer inaccurate (not just the usual complaint!)

My 2010 Taco, too, suffers from the often reported inaccurate speedometer. The faster I drive, the higher the inaccuracy of the needle.

I called my dealership about this, and they told me that "if they were to measure the computer it would also show this inaccuracy. It's within tolerable levels and nothing we can do about."

Well, this is not true. I recently received my ScanGauge and noticed that the MPH gauge is DEAD ON accurate reporting the speed of my vehicle as my GPS is, at all speeds. The speedometer needle, however, is still off.

This leads me to believe it's something they can and should fix. Has anyone else noticed this ECM read-out as well?

 

sounds like good excuse for larger tires

 

That's the usual remedy I've heard, but doesn't that contradict the fact that the ECM, which drives the speedometer needle, is actually accurately reporting the vehicle speed?

 

They probably could- but they aren't going to. There is error inherent in the digital to analog conversion and if that tolerance it met- Then there isn't a problem- just something you don't like.

If you have a GPS and a scangauge- Who cares if the speedo read correctly or not??

 

It's the principal of the matter. I've driven my share of cars, and moved my GPS from car to car in the past years (rentals, friends, previously owned vehicles, mine, the wife's), and I have just never seen a misrepresented needle. In 2010 that shouldn't happen to a brand new $30,000 vehicle. You're completely right: it's just something I don't like

 

Thinking about new tires, but I can't afford it just now. Haven't even made the first car payment yet and sunk over $2k into the truck already lol

 

If the scangauge and the GPS agree on the speed and the speedo is wrong- and then you put larger tires on it and the speedo shows correctly...You'll be speeding all the time. So like 5 mph over highway speeds will really be like 10 or 11 over....

 

Very true.

 

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Mine is off almost 3 MPH at 60. ..... Think of the money saved on warranty claims at 4%+ over-mileage on OD.

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That thought really, really bothered me before I got my SGII, but now that's no longer a worry of mine. Since the ECM is accurately reporting the speed of the vehicle, it stands to reason it is accurately reporting the mileage displayed on the OD.

 

That's exactly what Brunes posted earlier, and I suspected too. That will mess up your speed and odo readings, even though your needle might show a more accurate reading, your ECM is not.

 

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I am lost now ... how can the speedo be off and the odo be on target ??

Maybe I am thinking of the cars in the old days with the spinning speedo/odo cable ..
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So what kind of mileage based warranty did you buy?

 

What if my spedo and GPS agree and the ScanGauge is about 2-3mph slower?

 

You're in good shape. I think you can calibrate your ScanGauge to properly display your speeds. Think of your GPS display as the true measure of your speed. Also, your odo readings will be slightly in your favor

 

can somebody break my speedometer?