I put on a new starter and accidently cut the yellow wire that attaches to it, can I splice it and attach more wire to it so that it will reach? I took the wire out of an old car of mine so it would be the same wire but it's still not starting up my car will that cause it not to work?

 

What year is your car? I don't remember any yellow wires going to the starter. Should be 2 red wires that go on the same post as your positive battery cable, and a purple wire to the "S" terminal. But yes, you can splice a wire. There are several ways of doing it, but a butt connector of the crimp type with heat-shrink tubing over it should get the job done...

 

How about we start with the following;

-Year, Make, and Model of your Vehicle?
-Which Circuit (Yellow Wire) you are referring to: the Starter Motor Solenoid Activation Circuit, or the Starter Motor Power Circuit?

In addition, the following would be beneficial to know:

-Gauge, Length, and Type of Wire being used?
-Connections that the Wire makes?
-Use of a Relay?
-Use of a Fuse or Fusible-Link?

For the Future, let us know at least what Vehicle you have.
The better the Information that you provide...
The greater potential that the Information given back to you will be helpful.

Good luck.

 

Welcome to TGO
As stated more information is needed on your car as not all are wired the same, there's a lot of similarities but a 92 V6 and a 92 V8 can have quite a number of differences when it comes to the wiring. these cars being 30+ years old there's no telling who has done what to your car prior to you owning it, typically there are no yellow colored wires from the factory being terminated at the starter solenoid so there's a good chance that someone has already spliced in a wire to make a repair. Are you sure it's a wire terminated at the starter solenoid? Since electricity doesn't care what color the insulation of the wire is you can use what you have available, it would be a good ideal to either use the same color wire or make it correct to the drawings listed below. Making the connections for the repair are the most important part, soldering the connections and covering shrink tubing would be the best but a insulated/non insulated butt slice covered with shrink tubing will also get the job done.
The link below is a good reference to the wiring on the 82-92 F-Body
AustinThirdGen.Org (archive.org)