That’s a loaded question I did a multitude of things and I don’t know if any one specific thing fixed it or if it was a mix of all. But all I know is my manual and auto plunge has been 99% accurate for nearly 2 years *knock on wood*. That said, here.we.go...
1. I put (2) 1/4” E-clips on the elbow of the auto plunger to help keep it in place. One on the inside of the right arm, and the other on the outside of the left arm. I may have added a third to the outside of the right arm, but I was just looking at mine and it was really hard to tell if there’s an E-clip there or not.
https://www.marcospecialties.com/pinball-parts/20-8712-25
https://www.pinballlife.com/e-clips.html
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2. Loosened the exit lane guide screw and adjusted the lane guide accordingly. Tightened...tested...adjusted...tested...rinse + repeat. I recommend doing this with the upper right flipper removed or loosened in the up position (see step 3).
3. Replaced my upper right flipper with a lightning flipper.
I found that if my upper right flipper was in the way of clean and consistent shots. Not always, but most of the time. During my testing, I found that the shooter behaved much better with this flipper engaged (up position out of the way). So I replaced it.
https://www.marcospecialties.com/pinball-parts/20-9734-6
https://www.marcospecialties.com/pinball-parts/20-9734-5
4. Power settings:
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5. Lastly. And I don’t honestly remember what I did or I even changed anything (but I may have) so match my picture to yours. But, the metal guide is about a millimeter away from the black cabinet and level bubble. I think this helps the ball hug the guide for
It’s entire trip to the playfield.
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6. One other thing I did do early on before I did any of this other stuff was bend the auto plunge prongs that meet the ball. But I couldn’t get that to consistently help so I advise against it.
7. Step 7: pray to the pinball gods.
Good luck!