Alright, this one has me stumped. It's on a Road Show, and I'm hoping someone might have an idea as to what else I can try.

Right flipper is strong, and the middle and upper left flippers both work as I expect them to.

I've done everything I can think of:

1. New coil / full flipper rebuild / bushing / flipper bat / EOS switch
2. Confirmed 70vdc at every lug on the coil
3. Swapped flipper optos (L/R)
4. Swapped in a different Fliptronics board
5. Connectors on the Fliptronics board all look good, no discoloring

None of the change done made any difference.

I put in a stronger 11429 coil and I can now make the ramp shot (barely), but it's still soft and I'm pretty sure it wouldn't make the shot as the coil heats up during play.

The only thing I *haven't* replaced is the flipper plate itself. The plunger moves freely and doesn't get hung up.

I've been at it for 2 weeks now and am fresh out of ideas. So, what I have missed? Any other thoughts on things to check? I'd like to try to get this running properly and bring it to MGC in a few days. Thanks for any ideas!

Thanks for the responses!

The opto interrupter plastics are black. I just put the optos (boards and plastics) in an ultrasonic cleaner - no change. They're tight and not vibrating. I also put new flipper buttons on in case they weren't pushing the interrupters out far enough an also took some rubber rings and put them on the button shafts to make sure they were pushing out further and not vibrating. Left is still slightly weak.

Lloyd, the other bracket holding the coil and flipper plate are the only two things I haven't replaced. They look straight, but I'm wondering if they may be just slightly out of alignment and I can't see it. At this point I think I'm going to just swap those out with new parts and see what happens.

This isn't supposed to be that difficult!

Manually moving the flippers with the glass off, I don't feel any difference in terms of resistance moving them up or letting them drop back down. I think I'm going to just swap the brackets on the upper/lower left flippers and see what happens (since I don't have a spare plate around)!

Finally got around to replacing the plate and coil mounting bracket so the entire mech is brand new. It's smooth, so it's not mechanical at this point. Only thing left I can think of is replacing the female connector on the fliptronics board that powers the flipper, but I have a feeling that's not going to do anything.

Any other thoughts? I'm all ears!

I put in a new bat and flipper bushing - no change.

Solder connection to the coil itself is new, with freshly stripped wire. I swapped the Fliptronics board already with no change. Voltage tests good going to the coil. I think all that remains is rebuilding the connector on the Fliptronics, which is what I'm going to do next.

Thanks for the suggestions!

Interesting about the coil stop - I might just try that. With the stronger coil it's working mostly. Now, I did have a similar problem with a TZ after installing a ColorDMD. Weak left flipper. Thought it was due to a low 12v - nope. After replacing the bridge, cap and even the header pins still had a problem. Reflowed solder on flipper optos - nope. Then I swapped the flipper optos and they both worked again (but putting the board back on the left flipper caused it to go weak). My hunch at this point is there's a failing component on one of those flipper optos that is dragging down voltage on the other since they're chained together. At some point I'm going to buy replacement opto boards. Just another thing to try.

Brand new flipper opto boards - same issue. Replaced coil stop / bushing (again) / plunger / etc - same. EOS switches properly adjusted, and even completely disabling them didn't help. I said "I'm done with it" and put in a stronger coil which is working well enough - really frustrating.