Rpm gauge reading weird bouncing

[Nasser]

when i give my car full throttle in gear and watch the rpm gauge climb the needle bounces or shuffles a bit while its climbing. Anyone else had this happen before? ive got a new clutch and lightweight flywheel but it does not feel like the clutch is slipping when i just give it gas in gear so i don't believe its picking up slip on the tach or anything it feels like its getting a funky reading. Any input is appreciated.

[mandm177]

i know for the 20v, the tach is controlled by the coil, and if it's not grounded well enough, the needle will go crazy. See if that may be the case with the 16v.