89 RS w/2.8 just put this motor in a few months back, and all was working fine. The other day we had rain/snow mix and it wouldn't start (No fire), so I pulled it home and it sat for a couple days. went out to work on it and walla- it starts right up... but noticed that the tach was pegged (normal engine idle, but tack meter was peged) Since then it starts and runs fine, except for the tach which still pegs at startup (if you tromp it it will drop back to normal tach) I thought bad connection or corrosion at the coil, but I didn't find any...
any ideas???

 

bump

 

I have the same issue with my tach from time to time... if you rev it up a little, it will go back down to normal idle speed and act like it normally should. Never looked into it much though, didnt happen often enough for me to get worked up over it

 

thanks... If I find some thing, I'll let you know.