Tach problem
Thread Starter
Instructor
Joined: May 2007
Posts: 208
Likes: 0
From: Houma La
Tach problem
My tach has not worked properly since I own the car May 07.
It appears to run backwards. When I am cruising it is pegged and when i am at idle it comes up some. Some one who did work for me told me the distribitor is in 180 degrees backwards.... I run the car and it runs fine. Could I have tuned it to run with the dist backwards.
It appears to run backwards. When I am cruising it is pegged and when i am at idle it comes up some. Some one who did work for me told me the distribitor is in 180 degrees backwards.... I run the car and it runs fine. Could I have tuned it to run with the dist backwards.
Drifting
Joined: Nov 2003
Posts: 1,634
Likes: 4
From: Northern NJ
St. Jude Donor '04 & '05
100%Likely a bad circuit board. Many times when they indicate backwards it's a bad chip on the PCB. That chip is an obsolete part so if in fact it's bad, it may be difficult to repair w/o a donor board. You also could try an aftermarket replacement board, but many of those don't work properly either.
If you'd like more info on checking out your current PCB, please PM me.
Good Luck!
Team Owner
Joined: Jul 2006
Posts: 22,141
Likes: 4,156
From: Kannapolis NC
Let me know if you need a tach board that is pre-calibrated for a 78-79. I bought one and found a bad connection on the dash circuit board and never installed it. It comes with instructions and troubleshooting. I paid $75 plus shipping and I'll send it to you for $65 including shipping if you decide you need it. It's new in the box and never installed. It can be changed from the front without removing dash. If you aren't familiar with it and you need help, I'll include my phone number and talk you through it. Let me know.
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7th Gear
Joined: Nov 2008
Posts: 7
Likes: 0
From: Virginia Beach VA
I have done a bunch of reading about tach issues on here but now I have a question myself. I read about the filter that is attached to keep the circuit board from blowing due to voltage spikes. I have an accel distributor and it has 2 connections...one for bat and one for tach. I went looking and found a wire connected to the intake right in front of the distributer...it is yellow and looks like it would be connected to the distributor. On the tach wire that connects to the dist, there are 2 connections. Should that wire on the intake be connected to the dist or removed? Is it going to short out the board in the tach? Of interest is that when I go to start the car, the tach fluctuates and then pegs after it starts and is running.
Thanks for the help.
Thanks for the help.
