Hi guys, the tachometer on my 96' 115 Ocean pro is doing some crazy things. The old tach was giving me random readings and the pointer was broken off so, I bought a new Faria tach. I nstalled the new tach (the engine has the modular wiring for the tach) and I am getting the same results. It seems to work fine until around 4000 rpm then it drops to zero and stays there until I bring it back to idle. Some times it goes to 3000 and drops off. Where do I need to begin to identify the problem. Thanks in advance.