I have finally tackled the CEL codes P0410 & 1411 by replacing the cut off valve air injection. As some of you may know, this valve is under the intake manifold and dam hard to see, much less change.
I started by pulling off the alternator (look up a thread to find out how to do this). With the alternator out of the way, the valve is semi available to get at.
An alternative way to do this would be to pull the hose from the crankcase and the air pump, removing the whole hose assembly.
The biggest hassel is getting the spring hose clamps off. I will be replacing those with old school hose clamps.
Good luck.