Tach going nuts

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Mar 22, 2012 | 11:47 AM

lavatan

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Laughing Gas

Joined: Oct 2010

Posts: 997

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From: Rock Valley, IA

Tach going nuts

As some of you may know I put a factory tach in my truck. Wisely, I kept the aftermarket one in place.

So, yesterday I was driving to work as my Chrysler broke a timing chain, cam or something, and noticed the tach was fluctuating widly. Nothing else seemed to be wrong electrically and my aftermarket one is behaving normally.

Any ideas?

Mar 22, 2012 | 12:05 PM

ctubutis

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From: Denver Metro Area, CO

https://www.ford-trucks.com/forums/7...dywhompus.html

Mar 22, 2012 | 12:30 PM

lavatan

Thread Starter

Laughing Gas

Joined: Oct 2010

Posts: 997

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From: Rock Valley, IA

Thank you Chris. I appreciate it.

Mar 22, 2012 | 03:24 PM

Rogue_Wulff

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Joined: Dec 2007

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From: Lost

Was the tach reading super-erratically, both higher and lower than actual?
Or just not reading correctly and bouncing from 0 to near correct?
Different symptoms relate to different issues.

Mar 22, 2012 | 03:34 PM

lavatan

Thread Starter

Laughing Gas

Joined: Oct 2010

Posts: 997

Likes: 2

From: Rock Valley, IA

Hello Rogue. It was more the first than the second, it goes down to 0 but then spikes way above what it should be, but the second symptom occurs as well.

Mar 22, 2012 | 03:37 PM

Rogue_Wulff

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From: Lost

Start by checking the factory wiring for loose/corroded connections. If that doesn't seem to help, then you may need to dive back into the cluster, as described in that linked thread.