Tachometer is not accurate

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moses

Tachometer is not accurate

Post by moses »

In my '76, the tachometer is not accurate. When revving (in or out of gear), it moves, but stays within 2000-3000 RPM, despite knowing that I'm going higher than that.

I'm leaning towards it being the gauge itself, but could wiring cause this as well?

I have another thread related to the fast idle valve, could that being disconnected be related? http://www.fiatspider.com/f15/viewtopic ... 30&t=34107
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seabeelt
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Your car is a: Fiat Spider - 1971 BS1
Location: Tiverton, RI

Re: Tachometer is not accurate

Post by seabeelt »

Tach runs off the distributor. Check the wiring, but otherwise its the gauge
Michael and Deborah Williamson
1971 Spider -Tropie’ - w screaming IDFs
1971 Spider - Vesper -scrapped
1979 Spider - Seraphina - our son's car now sold
1972 Spider - Tortellini- our son's current
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lglade
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Your car is a: 1984 Pininfarina
Location: Mukilteo, WA

Re: Tachometer is not accurate

Post by lglade »

My tachometer was doing the same thing. It was the gauge. Someone was selling a new old stock one on eBay, so I replaced it.
Lloyd Glade- Mukilteo, WA
1984 Pininfarina Spider Azzurra
1962 Fiat 500D - wife's car
2015 Subaru Outback
2017 Ford Focus RS
carl

Re: Tachometer is not accurate

Post by carl »

Having a spider or X tach that reads right is like hitting the lottery. Some are off only at low rpm and some are off only at high rpm but I would rarely assume they are accurate. Think of it as more like an "engine running" gauge. Apparently most spider owners rarely rev their motors over 4,000 rpm and if the motor is stock probably loses power way before the redline.
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