Not running on all cylinders

[Jwaters]

Got a motor that no one can seem to figure out here. When it is running and you pull either one of the bottom plug wires off it almost shuts down. But when you pull any of the rest of them they don't make that much difference. I changed the coil pack around and it is still the bottom two that make the most difference. The compression is 105 in all 6 cylinders, and all the plugs are new.. ?????

[Bad Kitty]

I believe the V6 motors only run on 4 cyl below 2K rpms.

How does it run above 2K ?

[Jwaters]

Not very good. I had it out the other day when it decided to fire on all of them and I went from 4200 RPMs to 5300 RPMs. After it run like that for about 1-2 miles it dropped back out and slowed down.

[jb123]

what model
what year
what gauges
does buzzer work ?

[Jwaters]

1986 yamaha 150... If you are talking about the temp buzzer, no it dont.

[Jwaters]

would something like this be a bad power pack? and there is a little black box under the power pack, what is it and what does it do?

[Jwaters]

what is the small black sealed box at the bottom of the power pack?