Ive got a turbo timer that shows my rpm's and have been looking at that instead because the stock rpm gauge needle seems to jump every now and then and give false readings for no apparent reason.

 

it is broken

 

 

You need to take it apart and resolder it all.

 

Do a search
There is a fix for this, very detailed and very good
It is a pdf file
I do not have it anymore but many do

 

Either you need to take it apart and clean up the solder joints or it could possible be something up with the signal coming to your tach. I believe it gets it's reading from the primary coil, or is it secondary. My money's on the first choice.

 

i have the same deal... my PFC commander has a perfect read but my tachometer has some funky readings sometimes (false, bouncy, etc.). you and i both need to just take the damn thing apart and resolder all the connections.

 

Yeah I'll fix it someday, but I'm not too worried about it since I just go off my turbo timer's rpm mode. I got boost issues to take care of first.