'90 Tachometer Question Please!!??
Thread Starter
Pro
Joined: Sep 2003
Posts: 526
Likes: 1
From: Bowling Green KY
'90 Tachometer Question Please!!??
Hey guys and thanks for your help ahead of time. I bought this 1990 Corvette about a month ago and was told that the tachometer was not working. So therefore after having it for a month now and starting to get familiar with everything I happened to notice after a late inspection under the hood that the tachometer doesn't even seem to be connected to the plugs. I asked a local corvette technician over the phone and told me to look at a brown & pink wires right before the firewall and follow them to the "coil?" (all i know is the place where all the spark plugs connect at) anyways. I did notice a loose wire and also noticed where it says BAT & TACH is nothing is connected on the TACH side. Now I am gonna display a couple pictures and before I go plugging anything in does anybody have any suggestions here on how there car looks and if i can just plug this in? I need to grab a mirror so i can see under side of this but I thought posting pictures right off the bat could probably get somebody's ideas or help on this. Thanks!
Burning Brakes
Joined: Apr 2000
Posts: 980
Likes: 2
From: Chandler AZ
On my 90
On the 90 I had, the white wire was a pigtail that connected to a condensor looking thing that was bolted to the bell housing.
When I connected it, I got the tach working but it was very jumpy. I unbolted the filter (which was loose) and cleaned the connection. Rebolted every thing and used a star type lock washer and all was well. The tach worked great. I had the same coil as you as a matter of fact.
Luck,
When I connected it, I got the tach working but it was very jumpy. I unbolted the filter (which was loose) and cleaned the connection. Rebolted every thing and used a star type lock washer and all was well. The tach worked great. I had the same coil as you as a matter of fact.
Luck,
Thread Starter
Pro
Joined: Sep 2003
Posts: 526
Likes: 1
From: Bowling Green KY
After putting the wire into the connector the best I could, I then started the car and the tach came alive and went to 6k rpm and then went back down way below 0 to the resting point and never moved again when the car was revved or anything. Since there is life and it moved to 6k and back when the car started (like the c5 does when you start the car, only example i know of) but doesnt work, does that mean i need to clean the tach filter now?? Any advice please? THanks!
Melting Slicks
Joined: Jun 2006
Posts: 2,923
Likes: 1
From: Cleveland Tennessee
I think what that means is that you tach (guage) is working since you saw it swing to 6k then back to zero or below, so now you know that the guage works, that is one problem to eliminate. I have never heard of a tach filter?
Last edited by RonVette2; Aug 22, 2006 at 06:22 AM.
Team Owner
Joined: Oct 2000
Posts: 44,773
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From: 63.8% of all statistics are made up on the spot.
St. Jude Donor '08-'10
I'm not 100% sure of this but I don't think there is a tach filter on 90 model. I think it was on the early C4s only. I'm sure somebody that knows for sure will chime in.
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Le Mans Master
Joined: Feb 2005
Posts: 5,146
Likes: 3
From: The Motor City
Yes the 90 has a tach filter and of course it is hard to get at. It will be attached through a bell housing bolt at approximately 1 o'clock postion on the back of the block. It will look like an old style distributer condensor w/one wire in and out. You may need to remove windshield wiper motor or the dizzy to get it out.
Thread Starter
Pro
Joined: Sep 2003
Posts: 526
Likes: 1
From: Bowling Green KY
Well since I can't get to this just yet. The connector is connected and like I said the tach jumps to 6 when i start the car and then flips down back under the 0. Anybody have any other suggestions on how maybe get this to work?
