tach reads high

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Jul 24, 2009 | 06:29 PM

Diesel_Brad

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From: Gilbert, PA

tach reads high

In my Lightning, my tach reads 500-100 above where is should. Any ideas? O and it has the white face overlay in it to.

Jul 24, 2009 | 06:43 PM

DBGrif91

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From: Des Moines

How can you tell that the tach is reading high?

Jul 24, 2009 | 07:45 PM

Neptoess

Tuned

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From: Ohio

i'd like to hear this one as well. unless it's reading like 1500 at a noticeably normal idle, i have no clue how youd know unless you had a really good ear from years of driving sticks and staring at the tach

Jul 24, 2009 | 07:50 PM

Virto

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From: Des Plaines, Illinois

It's been said that the factory tachs aren't particularly reliable or accurate. Have you checked it with an aftermarket tach from the coil?

I've seen a number of theads where people have factory tachs running 200-500 rpm higher than aftermarket. I'm not sure if they were just built with poor tolerances or if they have a moderate-high failure rate.

I know the circuit paper in the dentsides rots away causing all kinds of problems. Not sure, but there might be some kind of poor connectivity with the cluster.

Jul 24, 2009 | 08:02 PM

Neptoess

Tuned

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From: Ohio

i wouldnt waste the money on an aftermarket tach unless you're doing competitive racing or something. most of the time you don't even need to look at your tach to know when to shift, it's more of a feel you develop. when trying to get absolutely perfect shifts though an accurate tach is almost essential.

Jul 24, 2009 | 10:56 PM

Diesel_Brad

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From: Gilbert, PA

Had the truck out tonight(only put about 3k on a year) The tach was reading about 2000-2500 at an idle. And no, it was not idling high, only about 700rpm