Shift light ground/pill question.

Fett

New Member
Nov 2, 2004
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I installed my Autometer shift light tonight, and it isn't working.

I ran the green through the firewall and hooked it to the negative side of my coil. I tapped the red wire into an ignition hot wire in the drivers side kick panel, and I ran the ground to one of the steering column bolts. I know that spot is a good enough ground for a test light, but I am wondering if it is not a good ground for the shift light. I tested power to the light and it is showing power with a test light, so I am pretty sure it isn't a power issue. I know the wire going to the coil is on the negative side, so I don't think it is that. I am wondering if I chose a bad spot for the ground.

The light comes on for a second when I start the car up, but it will not work with the 5000 pill I have installed. I reved the motor up to around 5500 and the light never came on.

It is an Autometer light but I am using MDS pills because I was told they will work.

I do have an MDS 6AL, but it is mounted just above the cannister on the pass side, near the front of the car. I didn't feel like running a wire that far. The coil was a straight shot.

Any thoughts before I tear this apart again?
 
Still playing with that light ? :) Since the light did come on when you turn the key that is good ,you have power and ground. That is a self test so it is normal. How about checking the back of the shift light and making sure it is on the 8 cylinder setting 4-6-8 . At this point I could only suggest you beg,borrow or steal one of those 3000 rpm chip that come with every MSD box. Most guy will have one somewhere around their house. That will be low enough rpm to test the light,the factory tech is just not up to snuff. So you might be still 400-500 rpm off and the light won't flash. Or just take it out with the lowest rpm chip you have on hand and take it for a test drive. The MSD and Autometer chip are interchangeable.
Good luck !
 
Chris, one other idea:
For grins, you could run a wire to the tach output on the ignition box (just do this on the outside of the car - unless your box is buried, it should be a one minute proposition) and try it that way. It seems to me that the multiple pulsing (though only occuring at lower RPM's IIRC) could cause some sort of issue with the shift light reading properly, no?

Good luck.
 
Chris, one other idea:
For grins, you could run a wire to the tach output on the ignition box (just do this on the outside of the car - unless your box is buried, it should be a one minute proposition) and try it that way. It seems to me that the multiple pulsing (though only occuring at lower RPM's IIRC) could cause some sort of issue with the shift light reading properly, no?

Good luck.


You were right again. You can't run the green wire to the coil if you have an MSD. Of course, it WAS in the instructions that I clearly didn't read. I did what you said and extended the wire and hooked it to the MSD box, and the light worked perfectly. So I re-ran all the wires and moved my light.....because I thought I would be clever and put in on the side of the center console next to the radio. You know, right where my knee blocks it from my view, which will be difficult to see during the day.

Funny thing, I noticed that at slow accel, the tach seems to be pretty accurate. But at high accel, the tach is off. If I slowly raise the RPMs to 5k (with a 5k pill), the light triggers almost right on 5k. But if I do it quickly, the light comes on much earlier. I am assuming that it is the tach that is not accurate at quick revs, and not the light.

Either way, I have 5000, 5200, 5400, 5600, 5800, and 6000. So this should help me with my times. I ran my best just listening to the engine, now I can make accurate shifts. If that, along with my new exhaust, doesn't get me a 12.99 pass.....my 75 shot should. :)
 
Sounds good man - glad it's up and working.

FWIW, I have an AM tach in the 88 (a lot of the time my forearm is in the way of seeing the stocker) and I think I've noticed a difference in the stock tach more during fast acceleration myself. It's like the thing is a half-step behind when RPM's rise quickly. When I putter around or just compare RPM's with little acceleration/deceleration or while holding RPM, the stocker isn't super far off. Shrug.

As long as your new light lets you be consistant, who cares (IMHO).

Oh, the knee blockage issue sounds like something I'd do. :rlaugh: I out-cute myself all the time. :D
Good luck at the track.