He says boat runs rough seems to be midd firing until he hits the trim then it wakes up. Almost seems like a drop in voltage makes it run right. Almost totally opposite from what I've ever experienced. I've seen them run fine until voltage drop THEN run rough (Like weak battery and insufficient charging)
Anybody else experienced anything of sorts?
Thanks
He should monitor the battery voltage with the engine running then hit the trim in both directions and look at the effect on the battery voltage . Could be a bad diode in the rectifier circuit is letting the AC current through causing noisy DC to the ECU wreaking havoc with the injection system . If you have a good multimeter that is capable of reading DC volts / hertz you can spot a bad diode (or with a fully charged battery you can disconnect and tape the rectifier wires , run the engine and see if the problem stops ). Perhaps the additional load from the trim motor is lessoning any noise ? Another possibility is a poor connection some where in the harness wiring is coming thru the trim wiring when energized forming a sneak circuit coming around the bad connection ?