'90 Tach Doesn't Work
Thread Starter
Pro
Joined: Sep 2003
Posts: 526
Likes: 1
From: Bowling Green KY
'90 Tach Doesn't Work
I need help on where to start to get my tachometer to work please.
There is a MSD ignition on the car and I have looked and read as much as possible and I do not know where to begin to help fix my tachometer. The tach when I start the car goes to redline and back down and thats all it does. Where should I begin?
There is a MSD ignition on the car and I have looked and read as much as possible and I do not know where to begin to help fix my tachometer. The tach when I start the car goes to redline and back down and thats all it does. Where should I begin?
Le Mans Master
Joined: Aug 2003
Posts: 9,884
Likes: 3
From: Magnolia Mississippi
St. Jude '03-'04-'05-'06-'07
Le Mans Master
Joined: Aug 2000
Posts: 8,838
Likes: 31
From: Australia
Have been lots of similar problems posted about tachos in the first of the new style dashes (1990).
My '90 does similar.
Don't recall any known "fix" other than try replacing the tach filter.
Black cylinder, two white wires mounted on bellhousuing bolt behind dist , dvr side.
I believe these are discontinued , 2nd hand only
My '90 does similar.
Don't recall any known "fix" other than try replacing the tach filter.
Black cylinder, two white wires mounted on bellhousuing bolt behind dist , dvr side.
I believe these are discontinued , 2nd hand only
Le Mans Master
Joined: Feb 2005
Posts: 5,146
Likes: 3
From: The Motor City
it has been stated that dependiing on which msd coil it will have an effect on the tach.........I am only using the in cap upgrade coil, and the filter can also be the issue, you can try wiring it w/out the filter to determine if that is the problem. If it is, you will have to buy used no new onesfrom GM for the 90, that I know of
Thread Starter
Pro
Joined: Sep 2003
Posts: 526
Likes: 1
From: Bowling Green KY
Guys sorry I am revisiting this so somebody else can provide some advice, ended up I was mistaken that I actually had an ACCEL coil and the tachometer still does not work. So what I did was go to local AutoZone and bought the cheapest tach and hooked it up as a temp test and put it on the coil where it says TACH and started the car and it worked perfect. I am glad it works, now I just need to figure out what is wrong with the stock tach. I plugged it back in and I get the tach to flip to redline and back at startup and fall to the very bottom and she never wakes up again.
Any suggestions?
Any suggestions?
Safety Car
Joined: Mar 2005
Posts: 4,723
Likes: 11
From: Winnipeg Manitoba, Canada
I have the same problem with my 90. The tach is way off inside the car, but when I hook up a tach straight to the distributer its fine. I tried with and without the filter and I get the same result. My instrument panel must be the culprit.
Thread Starter
Pro
Joined: Sep 2003
Posts: 526
Likes: 1
From: Bowling Green KY
Does anybody think this would help me get it to work? http://www.jegs.com/webapp/wcs/store..._145040?CT=999
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Intermediate
Joined: Mar 2007
Posts: 40
Likes: 0
From: Crestline Ohio
Jimmers.... I am in the same boat with my 90. With or without the filter it is still around double what it should be. I am going to try and change the bin. file... the previous owner put a ADS chip, in it.... I tune my own, (on all my other cars Trans Am, etc) see if that fixes it. I am running out of Ideas
Safety Car
Joined: Mar 2005
Posts: 4,723
Likes: 11
From: Winnipeg Manitoba, Canada
Jimmers.... I am in the same boat with my 90. With or without the filter it is still around double what it should be. I am going to try and change the bin. file... the previous owner put a ADS chip, in it.... I tune my own, (on all my other cars Trans Am, etc) see if that fixes it. I am running out of Ideas
Intermediate
Joined: Mar 2007
Posts: 40
Likes: 0
From: Crestline Ohio
1.I bypassed the filter,,, no change.
2. I installed a small cap Pro-Billet Dizzy (MSD, had one in my parts GTA)... no change
3. Factory bird coil... to msd... no change
4. build a T filter two 5.6k's and a .1uf cap... no change
any other idea's
2. I installed a small cap Pro-Billet Dizzy (MSD, had one in my parts GTA)... no change
3. Factory bird coil... to msd... no change
4. build a T filter two 5.6k's and a .1uf cap... no change
any other idea's
