Chrysler Repair: Catalytic converter plugging up?

Question
QUESTION: Hi Roland its Al from yesterday with the 03 dodge grand caravan  can you tell me if you would know what the symptoms would be if the catalytic converter was getting plugged up

ANSWER: Hi Al,
The symptoms of a plugging up catalytic converter are noticed primarily when the engine is operating at higher rpm and load which is when restrictions in the flow of exhaust gas would feed back to the combustion chambers of the engine and thus cause missing due to incomplete emptying of exhaust gas on the exhaust stroke. It would not be noticeable at low/moderate rpm and load. A muffler shop can test for that situation.
Thanks for the rating and nomination.
Roland

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QUESTION: Yesterday you mentioned something about the egr valve well this 03 doesn't have one any thoughts

Answer
Hi Al,
The egr not being used simply means that can't be the cause of missing at idle or when accelerating, if that is the problem. So unless you have a code for 'missing' then either it is too subtle for the pcm to notice it or isn't missing. So waiting for a code is probably the best thing to do in the meantime. You can simply keep try the key approach until a new code comes up.
Roland