hey i'm at idle the rpm gauge will just jump up to 3k and its really only idling at normal idle. any ideas what it might be? my problem was the trailiing ignitor but i fixed that

 

factory tach or aftermarket?
if it didnt happen until u changed it , check your igniter box ground and the wiring.

 

its factory and i installed msd but on the leading side. before i installed msd tho my tach wasnt working because of the ignitor and then when i changed it it was actually reading but now its reading all retarded. maybe if i change this one itll read good? says i'm idling at 3k lol