ok so my tach is acting crazy. im not very good with electrical so im hoping u guys can help me. as soon as i fire it up my tach jumps usually between 2 and 6 rpm. up and down quickly. any ideas?

 

Bad distributor cap potentially. Go to autozone, buy one, pop it on. If it fixes it, there's your problem. If not, return it. Search if you want more info on the dizzy and this issue

~Peace

 

thanks. thats a lot cheaper then i thought it was going to be. i was told it was probably a junk cluster but that just didnt sound right. ill try it out and let u know what happens..........

 

Dizzy controls the revs on the tach. Bad Dizzy = Jumping Tach. That's the most common issue that people have when getting the jumping tach. Good luck and keep us up to date. Sorry I don't have more info, but the search function should help if you want to know more of a technical reason as to why it happens.

~Peace

 

I had this same issue in my bb6. I changed the cap and rotor button, plugs, and wires to no avail. In my case, my egr valve was bad. Im not saying this to discredit anyone elses suggestions... just trying to point you in another direction if the dizzy isn't the culprit. Good luck.

 

I just run my tach off the A21-A22 ecu.

No more need for jumping tach crap

 

Could very well be a bad ground if not the dizzy cap.