Chrysler Repair: Code PO403 EGR Malfunction, mechanic work, narrow pipe

Question
My service engine light came on and I went to Advance Auto and got the code pulled, it was PO403 EGR Malfunction.  How is this repaired?  My brother does mechanic work and told me it sounds like the Catylatic converter is clogged and may need a new one, could this be causing the problem?
Thanks for your help!

Answer
Hi Calvin,
I have to suggest an alternative to your brother's opinion. The egr alone can be faulty without having anything to do with the catalytic converter, in fact the egr taps off the exhaust manifold upstream of the converter and the converter has codes of its own. The egr is a vacuum/electrical solenoid-operated valve and because it is
feeding exhaust gas back into the intake manifold it can buildup exhaust crud at the valve opening and valve stem which prevents it from opening and closing in a prompt and reliable manner. So my experience is that if you will find the valve and its stem you may be able to free up the operation by merely putting some WD-40 on the stem where it enters the valve and then with the tip of a screwdriver inserted in the slot of the stem move the valve stem in and out so as to free up its motion. If that doesn't help to resolve the code then removing the valve and cleaning out its throat is the next step, and finally if it seems to cruddy/damaged then to replace the valve. You didn't mention which engine you have so I can't describe exactly where to find it but there is narrow pipe from one of the exhaust manifold(s) that runs back to the throttle body intake manifold and along that pipe you will find the valve.
Roland