You would Notice Poor running like without it. Maybe even Popping out the exhaust Leaving off the throttle when it Never before.
Dobeck's told me that the TFI had VERY Few go bad OVER The Years.....
Are you having a Problem?
Personally I have (know) many out there and NO Problems.
Try this;
IF you want to check your TFI. Take unit out of hiding and open the rubber,,,,,,, Running motor at idle,,, turn UP for more fuel,,,, It should Flood out then reset to the good running as before...Note the position it was in BEFORE you move pot one Open...:s
That will tell you IF it is working...
signed....BUBBIE