D180 tach help

[pjwatson]

I have a Lyc. IO360, and my D180 tach is bouncing from 2200 to 3100. I have 33ohm resistors in line (P-leads). Should I change to a higher resistors?

 

[dynonsupport]

Do you have 33 ohm or 33,000 ohm (33k) resistors? What kind of ignition?