Speedo and Tach are wrong

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02-28-2019, 06:53 PM

RBSDISCO

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Speedo and Tach are wrong

1998 D1 85k gas v-8.
Plugged in the Code reader and my tach and Speedo are both off, I read that the alternator has a lot to do with the tach so I made sure the white wire was plugged correctly into the alternator which is 3 months old from RoverFarm. Any ideas why they would be off?
Thank you very much.

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02-28-2019, 08:33 PM

stillruns

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1998 w/85k..noice!

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03-01-2019, 07:39 AM

RBSDISCO

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speedo and tach

It could be real nice if I could get the last 3-4 things handled, that 3-4 was 18-19 it’s taken a whole lotta time and and little money. Oh yeah and a parts car 1998 Black D1. You know about this issue?

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03-01-2019, 07:40 AM

WaltNYC

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How far off?

Speedo is generally 6% fast on the dash with stock (16/70-235) tires.... meaning if you see 70 on the speedo, you are probably travelling 66 mph if measured by GPS.

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03-01-2019, 07:51 AM

stillruns

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Like Walt said I don’t think they are every truly accurate. I’ve owned two, current one is a 98 with 89k miles and the speedo kinda ups and downs slightly. It works fine but it isn’t like my 4Runner where it stays exactly in place with the mph. I’m running stock tires also.

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03-01-2019, 08:39 AM

jimvw57

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Looking at my code reader, it says I am traveling at 53 mph, speedo says 65, GPS says 60. which do you want to believe? My code reader shows a lot of spikes and dips so I am guessing my speed sensor may not be in the best shape, I have a new one but I am waiting for the weather to get above 20 degrees before I crawl under and install it.I also have tires a size larger than stock

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