Max, you are right. I have seen a few busted up cats that caused weak
power under load and a couple that kept the engine from running much at
all. I helped find one of those after the family mechanic had given up
and wanted to light the thing on fire. I'm not sure how to generally
test for the failed cat condition though. Sometimes the cat pieces only
get blown into a blocking position under high throttle and sometimes
they stay there.

I brought up this thread mostly to put the idea in more minds that this
is something to watch for. Unfortunately the bolts that hold the cat and
muffler are often so rusted that a destructive tool is the only way to
get in there to check the cat and people shy away from that.

Mark

Max Wellhouse wrote:
> Mark: I nthis age of Catalylic Converters, I think we need to modify
> that old adage of checking for Compression, fuel, and spark and add
> "breathing".
>
>