I have a 2007 extreme shallow with a yamaha 160. I bought the bought used a few weeks ago. i put about 10 hours on the boat without any problems. I now have 111 hours on the motor. The 4th of July weekend I put the boat into the copper river for dipnetting. We did well on the dipping part of the trip. I tied up to the rocks or put the boat on shore a few times and when I started up the boat the engine stalled out a couple of times. Then when I made my run back up the river the rpms would drop down a thousand or 2 rpms then go right back up to the 10,000 rpm. When I got back to the boat landing the engine stalled out again. We floated the boat onto the trailer and I started the motor 1 more time and got the boat all the way up on the trailer. The spark plugs are old but not are carbon up. I have looked for a fuel filter and could not locate a filter. I am thinking the filter is in the gas tank. The other possible problems I thought of is fuel injectors or some type of relay problems. Is there a wiring harness hookup where a diagnostic tool can be attached to troubleshoot this problem. Any ideas or help on solving this problem would be appreciated.