Okay, well I probably wont get too many responses but(hey i was wrong, hahha). Anyway, I installed one yesterday, and it works right off and on, lol.

It was working fine today till I tried to hook up vtec and ground off the switch at the same spot I did the tach. Now I know you guys would think, "Check ground", but I did like 900 times.. What the tach does is like when I am driving normal, not ragging it will be fine, no jumping around, but when I nail it, around 5000 RPM the autometer tach only jumps around a lot. The stock tach dont move around, it stays, so its not the ignitor, only thing it can be is the power source or something. Ground or hot? I would think more ground, but.. Anyone ever had htis problem?


[Modified by CimorelliCRX, 10:06 AM 10/5/2002]

 

i have the same problem. i also disconnected the stock tach and just hooked up my aftermarket one, same exact problem as you (tach goes nutz above 5k rpm when you are WOT).

i couldn't figure it out. i haven't spent much time trying to figure it out. just hooked the stock tach back up and will use that for now.

 

Where are you guys hooking up the signal wire for the tach? When I installed my shift light I first tapped into the signal right at the gauge cluster, whenever I hit the shift light's RPM, the factory tach would jump like crazy and die out. I had to tap into the signal al the way at the distributer, their wasn't enough voltage when I was at the gauge cluster to keep the two seperate things working at the same time.

 

mines jumps every now and then... and its bc the wire that gets the signal gets a little loose,,, make sure u got that blue cable tight and making good contact....

 

You pretty much have to tap into the wire at the distributor. Its way more acurate and Isnt that hard to do.

 

This could be a early sign that your ignitor is on it's way out or the ignition coil. Same thing happened to me and after I changed the ignitor all problems went away.

 

Well I know its not coil or ignitor, because the stock tach is fine. ITs just the autometer tach. After 5k it jumps like crazy. I gotta figure it out, its a bad connection somewhere i am sure. I have an autometer shift light in my other car, and it works fine.

 

I wouldn't rely on that theory too much. I have an autometer tach and a stock tach, I have had a bad ignitor in which the autometer started jumping around indicating a possible bad ignitor, way before the original tach showed me any signs of a needle bouncing. After replacing the ignitor both worked just fine. Check all the connections in the dizzy also. I found that the autometer is not neccesarily more acurate but alot more sensitive than the stock tach.

 

definitely a loose connection.
solder the biatch.

 

mine did that when the dizzy was loose

 

the true tach signal is the blue wire at the distributor. make sure you solder all connections and this with a proper ground and 12volts should cure your problem with your tach. goodluck

 

Im gonna mess with it all day long to get it right. I am sure after about 5 hours of messing with it, I will get it fixed, lol. No but seriously, when I figure it out I will post what was wrong. I am still saying bad connection.

This is where I have everything wired too...
Red and White wires are wired to the clock positive wire
Green is wired to the blue wire at the coil
Black is wired to the stereo ground.

I had easy access to all these since my intereior was stolen, lol, i just cut the clock wire and the stereo wire was already for the ground...

 

ground the ground wire to the chasis, not to the stereo ground. that could be your problem. goodluck with troubleshooting

 

Well today I was thinking.. I used to have a sunpro dragon tach, and I thought to myself, what was the problem when this was it last time and i fixed it. Guess what, ignitor. And this was the same problem. I knew the ignitor couldnt be bad cause i had replaced it. But one of the wires was barely making contact on the ignitor, which was the problem. Its all fixed now.

 

I have the same problem but both of my tachs jump around at like 6500-7200 and the go nuts both stock and regular i see a lot of people think it is the ignitor where is the ignitor