Tac acting erratic
Thread Starter
Melting Slicks
Joined: Feb 2008
Posts: 3,412
Likes: 118
Tac acting erratic
I've been shopping for a C3 and one I drove today that I was somewhat interested in I noticed the tack freezing at one point and at other times jumping all over the place and even at idle setting on Seven Grand. I am thinking a wire is shorting out or possibly an alternator issue however the gauge for the battery seem to be normal. What do you guys think? I'm still interested but don't want to get into a lot of problems with a car.
Le Mans Master
Joined: Aug 2017
Posts: 8,336
Likes: 2,809
From: Cool Northern Michigan
I would bet that the issue is the Tach Filter. Its a cylinder shaped canister that looks like a condenser with two wires coming out of it. Its usually bolted / clamped to the intake. The wire leads become damaged or come loose causing the tach to have a mind of its own. As I recall those filters are not cheap but sometimes they just need to be removed, put in a vise and re-solder the connections.
Former Vendor
Joined: Aug 2006
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From: Jeffersonville Indiana 812-288-7103
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
I've been shopping for a C3 and one I drove today that I was somewhat interested in I noticed the tack freezing at one point and at other times jumping all over the place and even at idle setting on Seven Grand. I am thinking a wire is shorting out or possibly an alternator issue however the gauge for the battery seem to be normal. What do you guys think? I'm still interested but don't want to get into a lot of problems with a car.
Last edited by Willcox Corvette; Jul 17, 2018 at 08:41 PM.
Thread Starter
Melting Slicks
Joined: Feb 2008
Posts: 3,412
Likes: 118
Thanks for the replies I wasn't aware that there was a tac filter. That helps. The car is a 75 with 61k miles and one owner. It has new tires and claimed new brake calipers but it acted like it was only stopping with the back brakes. The air needs charged and the radio doesn't work. Other than that it needs paint and the interior redone. I have been shopping around and this one rode better than all others I have looked at. The dealer offered it to me for $8,900. There's bound to be other issues pop up and I'm just not sure it's worth that much money with what needs done.
