bhbodily

I just purchased a 2002 Accord, EX with the V6 engine. The check engine light has come on with the P0401 (EGR insufficient flow) code. At the same time the light comes on, so does the TCS light. This code is 31 (engine retard command).

I've taken the intake manifold off twice to clean the passages in the upper manifold and then the lower passage down to the EGR valve. I've also replaced the EGR valve just in case something was stuck there. So I'm pretty confident the passage is clean. But the lights keep coming on.

The CEL and TCS light come on when I decelerate or break after driving at freeway speed. For example, I can drive at 50-60 mph no problem. But when I take my foot off the gas to coast, or enter the off ramp and break this seems to trigger it.

The CEL then stays on but the TCS comes on intermittently. And the TCS seems to come on after the same driving sequence outlined above. After driving at a high speed (the engine under load at ~ 2000+ rpm) it will come on when the load is removed and the car either coasts or the brake is applied.

Any ideas as to what is causing this?