Quoted from luckymoey:
Thanks. I did change the coil sleeve and cleaned up the stop which was still in good shape. Also increased coil power a few notches with no effect. I'll take a closer look at the wire form but it's well seated in the playfileld and the ball is only traveling several inches up during mis-fire. The baffling thing is that it works perfectly in test mode - dozens of times in a row. I even fed balls into the shooter lane quickly during test to try to replicate multi-ball. I may need to take the Koop gun barrel off to video.
I’ve always had the same symptoms you’re describing, including it working well in test and happening more often in multiball. I haven’t taken the time to check it out though (sometimes I’m relieved to have a couple extra seconds before adding the ball). I’ve suspected the washer on the ball guide screw that overlaps into the shooting lane is interfering with it based on the wear on the washer, but now I have another idea too. Here’s a link to a post with a picture of the washer I made about this a few months ago.
I’ll take a look at it this weekend. A similar thing started happening on my JP2 and I figured it out a bit so I want to see if the same thing is happening on my POTC. After about 150 plays of JP2 not missing an auto launch it started missing somewhat frequently. I started checking it out at the start of a new ball. I realized that most of the time the ball came to rest with both sides of the auto launch touching each side of the ball, but sometimes one side of the auto launch would be slightly off the ball.
That game can launch a ball with the action button, so I started looking at how the ball was resting on the auto launch fork and then using the action button to fire it to see if there was a correlation. It seems pretty certain there is. I’ve been able to predict pretty reliably prior to launching whether or not it’ll get through the flip ramp based on whether or not both sides of the auto launch fork are touching the ball. There must be just a very slight amount of play in the launch fork that causes it to have both sides touching sometimes but not other times. I’m thinking that could be going on for POTC too, so I’m going to see if there’s a way to tighten it up slightly.