Is that part of the tach. In the dash? Could I install an aftermarket one? I don't really know anything about this subject.
Yes. IIRC, the tach has 2 chips on the back of it - this is why the whole cluster must be removed to work on it - that have contact points.
The solder, according to this video, points become brittle/hair line cracked and the current is nothing or inconsistent going through it.
Installing an aftermarket one was one of my questions in another thread.
I linked a video of a guy that had installed one. He didn't document how he did. He only states the tach must read "pulse" and be set to "something" which I cannot recall.
So I was looking on summit racing website yesterday. Gonna look at Jegs right now and maybe call them today to find out.