It is ideal to have them both with the same color dot, but usually after all these years, most likely the pressure sensor has been changed and the only one available is one without a dot. On both my D-jet cars, the dots don't match (and I have tried to find the pressure sensor with the red dot, no go), but the cars run fine. The CSL has the red dot CPU and blue dot PS. From fiddling with my system, I have found so many variables that could affect the car, but one of the most obvious ones that have always made a change was the trigger point, and the throttle switch.