My water pump had died and was leaking so i change it, now my Tach is jump around wildly and there a strange noise coming from under the hood. The noice started when the WP had started leaking fluids shouldn't it have stop now?? What else could make a tach jump around wildly?

 

What car is this for, what engine, what induction, tranny.... Can't really tell you much if we don't know what you have.

Also please re-explain your first post, i makes no sense, i got water pump leak and tach flutuating.

 

You probably have a loose plug wire.

 

84 firebird 305 v8. My tach was flutuating and there was a strange sound coming from under the hood. I check everything out and found out my water pump was leaking. So i chalk it all up to the Water pump going bad. Now i just got the water pump fixed and there's still this strange noise and tach it still flutuating. What else would make this happen?

 

Check your plug wires, thats exactly what happened to me when one came loose. The tach needle bounced around and the engine ran and sounded funny (duh, lol)

 

What car is this?

 

distributor maybe