Update for St owners. This was in a stle, but I'm gonna gander it is on all models.
Having had issues with my entry opto on the left ramp I have been going crazy trying to clean, adjust repin, etc etc and to no avail.
Finally removed the assembly tonight and found out a hidden culprit that all machines may be victim to one day.
The pair of optos on the ramp have both wires very tightly zip tied together in the ramp (out of sight). My initial problem with the opto was vibration, bit having tried to fix it so many times the wire became more taught and the zip tie only became a mystery and invisible hinderance.
I removed the vengeance ship and found the zip tie only once I couldn't pull the opto wire out without pulling on the opposite side.
If you get lucky, you can sneak mini snips in from under the pf and carefully chop the zip off the wires. This allowed me to remove the "faulty" opto.
I decided to test it else where and see if it was salvagable for parts and maybe it was a wire short or something. But now removed and no longer being pinched and pulled down, it worked fine.
So I reinstalled it, leaving the wire loose and using a different drop hole this time, it seems to be completely fine and functional again.
I reassembled everything and so far it seems my issue is totally gone. I'm thinking the tension and added pressure may have cause the opto to physically be moved and angled enough that the sensor was tripping non stop.
Just food for thought for any of you guys experiencing similar problems.
Wall of text over.