Recently i've noticed my gas gauge stays at full & my tach stops when I
turn on my lights. I show a tech article on a common ground problem
that causes this. It said to locate the solid orange #15 wire at the back of
the tach. it also said you can locate this wire behind the drivers side kick panel in the smaller wire harness. I chose the kick panel location ,so as not to pull the cluster out. i actually see 3 solid orange wires.I tapped into one
of them & re grounded(which the article led me to believe i would only
find one orange wire)after tapping into one of the wires the tach worked
with the lights on put jumps around a bit. I don't see any change in the gas gauge. Can anyone help with this.

I had the same problem, as did many other people on this site. I never heard of the kick panel wiring harness to be an option but it might be. I pulled my cluster out(including the dash) to fix the problem. There is only 1 orange wire back there so its not very confusing. I just regrounded it to a metal screw in under the dash and everything worked fine after. Its not too hard to pull the dash out(that is what most people try to avoid). Its just takes a little time and the removal of a lot of screws! If u do it ur way, u probably will have to reground all 3 orange wires. After I fixed mine, the tach did jump around for a couple days when i revved it up because of the magnetic force it creates, but went away a couple days later. It should go away soon after. Hope this helps!

Does regrounding the tach wire have any effect on the gas gauge.

Yes. Regrounding the wire behind the cluster will fix the tach and the gas guage. Until then, ur gonna have to use ur trip or odometer to tell u how much gas u have. I average about 300 miles per tank.

This is a really easy repair to do. First of all I have heard of the hunt for the wire technique. I do not reccommend it. Here is why:

http://img.photobucket.com/albums/v127/skymasteres/Mark%20VII/DashTachLight04.jpg

In my opinion you are much better off removing the 3? scerws (I can't remember) that hold the trim over the intamint cluster and the 3 screws that hold the cluster.

http://img.photobucket.com/albums/v127/skymasteres/Mark%20VII/DashTachLight01.jpg

http://img.photobucket.com/albums/v127/skymasteres/Mark%20VII/DashTachLight02.jpg

Once you have it unscrewed, just pull it straight out, unplug the harness, and reground the wire. The reasemble. Enjoy a working gas gauge and tachometer.

Thanks guy's .I'll take care of this over the weekend & get back to you Monday

I regrounded the tach wire behind the cluster. I not sure if i have a new
problem,but my car is not getting spark. It cranks & at times seems like it's going to catch. I bought a new distributor & installed it . It started up & ran
for a minute .Then went back to the same problem ,cranking ,but no spark
I never had this problem before.

I regrounded the tach wire behind the cluster. I not sure if i have a new
problem,but my car is not getting spark. It cranks & at times seems like it's going to catch. I bought a new distributor & installed it . It started up & ran
for a minute .Then went back to the same problem ,cranking ,but no spark
I never had this problem before.
Congratulation and condolences.

They shouldn't be related.

Did you verify that you're not getting spark to the spark plug wires by hooking up a timing light or test light? If your test equipment is flashing then you need to verify fuel. How much fuel pressure do you have under the hood?

Just completed this repair on mine. Easy fix, and one I would have spent a ton of time finding. Thanks to the forum, and to all who've figured this one out.