P401 code.....grrrr!!!!!

[98malibu3.1]

I have been getting a P401 Code "EGR Flow Insufficient" for a couple of months. It's intermittent and only comes on when it feels like it. I took it off last night and had a look. It didn't really look very dirty but I sprayed the inside of the ports with degreaser and sprayed some down in the tube that goes to the exhaust manifold and shot some into the intake port as well. I let it sit for about 10-15 min and put everything back together. I'm going to wait a while and see if that code pops back on. Anything else you'd recommend doing to make it stay off?
98 Malibu 3100

[3400-95-Modified]

Pipe cleaner through the passage to make sure its clear... those clog up pretty good.

[98malibu3.1]

Which passage? The pipe that goes to the exhaust manifold? What do i use to clean it out? One of those long metal rods w/the brush at the end? Is there any way to eliminate the EGR and be done w/it and not have the pcm throw a code?

[3400-95-Modified]

Cant remove it without a programmer.

Clean the passage between the plenum and the EGR, that clogs the most.