ISX Fuel Actuator

[bsiddle]

Afternoon everyone,

I run into a problem that I'm having no luck figuring out.

I have an ISX 871 that idles very rough. I know this because I have the same (same year model, year) motor in another truck.

So far I've checked all hose connections, changed the fuel shutoff value and changed, filters several times (been doing this for a while).

I started unplugging each actuator, one by one, and noticed a change in sound. It actually idled better with one unplugged than all plugged in.

Occasionally, the fuel delivery pressure light will come on, but it usually goes off within seconds. It does this even with the tanks completely full of fuel, so don't think it's a pickup tube. It also doesn't lack power, so I haven't changed any hoses. But, it will belo black smoke when you get into it hard.

Any thoughts?