Jumpy tach


Active Member
A little while back my tach just started acting jumpy out of the blue, I basically cant tell what rpm im at. Seems like scanmaster is reporting the right rpm so whatever is feeding the ecm is ok.

both my autometer tach and the indash tach are doing this, does the tach signal come off the crank sensor? Reason I ask is because I degreased the engine and the tach started working almost correctly for a little while and I do have an oil leak thats soaking my crank sensor.

Any ideas?