My truck is a 2006 F-350 6.0L. It's been getting a P0401 (Insufficient EGR Flow) since I bought it a couple of months ago.

I was hoping to just take it out, clean it off and be done with it. I took the EGR valve out and it barely had any soot build up on it (still 95% shiny).

While checking every EGR PID available in ForScan, I'm seeing something that doesn't quite make sense to me.

After I start the truck up, the % values for EGR Desired and EGR Actual are pretty close (~12-13%). The strange thing is, the EGR_OBDII_Commanded climbs up to 29.80% and stays there. If I rev the motor (in neutral), that value will come down but it climbs right back up to 29.8%.

While it was out, I started the truck and I could feel the exhaust coming out of the intake manifold (so I know it isn't blocked). The V PID (can't remember which one it is) changes with moving the plunger in and out. I can also see it move when the V value changes.

While driving, the %Desired and %Actual eventually go to zero and the V PID goes to and stays at ~0.84.

The truck has the original flash in it (VXCF1D6). Also still has EGR cooler.

Any ideas why the EGR valve wouldn't be making it to the commanded %?

Thanks