I'm thinking my 8912 Tach Adapter is going out. Since this has been discontinued for quite some time, do you offer repair service for this part? Or is there an alternative solution? My car is 1998 Ford Contour 2.5 V6, with DIS-4 Plus and 2x 8912 Tach Adapter. Thank you. BTW, I've tried tach #89121, it'll hesitate and miss around 3K-5K RPM.