The program on this engine automatically revs up when you first start it. When I remove the load its going back to start up mode. I just can't figure why it bogs to begin with. The exhaust is rich with fuel like its drowning in gas. It has a throttle plate that the computer reads for correct mixtures maybe for some reason they are getting mixed signals. I'm not sure how to check that.

Gene

I hear that the engine revs up considerably. In the first part of the video, it is running slower, then suddenly it revs up and sounds a bit funny, but it still seems to run OK. I would guess that is a governor problem. It certainly does not sound like a bad standard part (plugs, wires, PCV valve, carb or EFI, etc).

So this engine does not have a pcv valve. it has a vent that goes straight into the fuel injection.
here is a video of it doing its under water thing. it was at 1900 rpms when this started under load. to fix it i set the engine to 900 rpms and turned off the pump which removes about 5hp. it then self corrects. it is not the computer because i have 2 and it happens exactly with both. i reprogramed one just to be sure and it doesnt help.

http://youtu.be/8wVImu2wQKc

Did that underwater thing again. Next time I will try to record it I will check the PVC valve

Gene

Nissan coil part number 22433-11M00.

I can re-gap at .039 although It runs smooth as silk except the little hick-up. I do think its well over do for a new coil and spark plug wires. Which coil should I get

Gene

It does not use a standard coil, but uses a Nissan high-energy coil. From the symptoms you describe, I am certain it is not caused by the coil or the spark plug wires.

.044 is quite a large gap. The -11 plugs are gapped .039-.043.

It is fuel injected so I know it's not the carburetor however I never thought of the pvc valve . If I shake it should it rattle. It's been so long I can remember. The ignitor did help now it doesn't sound like its underwater any more or at least it hasn't repeated itself. Now it seems to want to die and then it's just fine again. The engine typically runs for 2-5 hrs at 2500 rpms under a heavy load . Then on to the next job and repeat. It's a ghost problem I can't make it happen and now it last for less then 1 minute and solves itself. I did go ahead and replace the spark plugs with NGK gr4 gapped at 44. It still has the original coil and wires but they seems fine. It has been the best engine I ever owned . Does it use a standard 12 volt coil. No harm in replacing it.

Gene

I suspect the carburetor.

The distributor is the stock 1990-up Japan unit.

Hows the PCV system on it?
I once blocked off the port in the rocker cover, and when the pcv valve sucked the hose flat, it stumbled right down to bugger all revs.