Tach Slow / Lagging

serafins

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The tach in my '99 is very slow to sweep when revving. When driving aggressively to redline, it shows about 5k rpm at the time I hit fuel cut.

Fuel cut is verified at prefix at a true 5950rpm. So the tach is lagging about 950 rpm. If revs are brought up slowly it will show the correct rpm.

Prefix told me this was normal. However, this is not acceptable to me and I refuse to believe it can't be fixed. Has anyone rebuilt their tach with a tach motor out of a newer tach? Is there some other fix for this?
 

ViperFan1

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I had this issue last summer on my 99. Went through so many different things and 3 different shops to check the car over, fuel pump, filter, O2's, wires, etc etc. Just ordered a new tach off eBay I think for like $140.
 
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serafins

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I had this issue last summer on my 99. Went through so many different things and 3 different shops to check the car over, fuel pump, filter, O2's, wires, etc etc. Just ordered a new tach off eBay I think for like $140.
Did you get a NOS tach or just another used one?
 

Steve M

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I've always used shift lights, but realize that many don't like them for various reasons.
 
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