Tach Question
Thread Starter
Instructor
Joined: Jan 2004
Posts: 152
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From: Wilmington nc
Tach Question
I recently bought an 82 Vette and my tach is not working, never has for me.
I did a tune up on the car this weekend (Stupid plug wires through engine mounts....that the heck is with that?? :mad )
Any way I found 2 white wires coming off of the tach terminal on the dist cap.
One plugs into another white wire and the other goes into a little canister, then out the other side and goes no where.
Where should that wire go, and could this be my problem, or am I barking up the wrong tree?
I did a tune up on the car this weekend (Stupid plug wires through engine mounts....that the heck is with that?? :mad )
Any way I found 2 white wires coming off of the tach terminal on the dist cap.
One plugs into another white wire and the other goes into a little canister, then out the other side and goes no where.
Where should that wire go, and could this be my problem, or am I barking up the wrong tree?
Pro
Joined: May 2003
Posts: 601
Likes: 0
From: Nottingham
Re: Tach Question (Blue70)
The two white wires are indeed the feed for the tach. One has a plug on the end of it to allow you to put an aftermarket tach on, say for a tune up, so you can read rpm under the hood.
The other is supposed to be the feed to your dash tach. The canister is an RC filter, to prevent voltage spikes reaching the tacho's delicate circuit board. This stops the needle from jumping (and eventually the board from frying).
So the other side of the canister, the wire goes nowhere? Does it have a connector on the end? It should have a (male?) spade connector. Somewhere poking out of the loom near the wiper motor should be another white wire with a corresponding connector. Hook em together and see what happens. If nothing, then the tacho circuit board is fried, or the filter is dead.
:cheers:
[Modified by theoUK, 12:00 PM 2/9/2004]
The other is supposed to be the feed to your dash tach. The canister is an RC filter, to prevent voltage spikes reaching the tacho's delicate circuit board. This stops the needle from jumping (and eventually the board from frying).
So the other side of the canister, the wire goes nowhere? Does it have a connector on the end? It should have a (male?) spade connector. Somewhere poking out of the loom near the wiper motor should be another white wire with a corresponding connector. Hook em together and see what happens. If nothing, then the tacho circuit board is fried, or the filter is dead.
:cheers:
[Modified by theoUK, 12:00 PM 2/9/2004]
Thread Starter
Instructor
Joined: Jan 2004
Posts: 152
Likes: 0
From: Wilmington nc
Re: Tach Question (Blue70)
OK
The one that does not go to the filter was plugged into the white wire from the harness, the filter was plugged into nothing.
So it's probably dead hu? :cry
The one that does not go to the filter was plugged into the white wire from the harness, the filter was plugged into nothing.
So it's probably dead hu? :cry
Pro
Joined: May 2003
Posts: 601
Likes: 0
From: Nottingham
Re: Tach Question (Blue70)
Ah, That's a shame. Either the tach stopped working and someone thought they'd try and bypass the filter to see if that got it going again, or (more annoyingly) some one bypassed the filter for no good reason, and it was that which killed the tach circuit off. You can buy new circuit boards - In fact the later c3's are apparently by far the easiest ones to replace. I did mine in under an hour, all from the comfort of the drivers seat!
Get in touch with Redline http://www.redlineg.com/
They don't advertise their new boards on the website, but they do sell them. About 60 dollars I think.
Many people say the filter isn't needed and to remove it, but I'm inclined to think it is. To my mind, if you've just bought a new board, then not protecting it with the filter seems a bit daft.
Good luck with it..
:cheers:
Get in touch with Redline http://www.redlineg.com/
They don't advertise their new boards on the website, but they do sell them. About 60 dollars I think.
Many people say the filter isn't needed and to remove it, but I'm inclined to think it is. To my mind, if you've just bought a new board, then not protecting it with the filter seems a bit daft.
Good luck with it..
:cheers:
