Clogged pre-cat

hiya, was just wondering if anybody had any experience with clogged pre-cats?
Long story short, s4 had an intermittent misfire. Not sure for how long, I recently baught it. Anyways, fault coded it found the 2 injectors and replaced. All well since. Took for a good drive for the first time in a while and about an hour in after everything was pretty hot had the same feeling of a misfire but only under load. Felt fine at low revs and low speed but if you put your foot down you could just feel it.
Plugged it in and no fault codes. No engine check light.

Wondered what the chances of the pre cats being damaged is from previous misfire? Sorry for the long winded post!!

gavmatt1978 said:

I had blocked precat, started loosing power, couldn't place it, no codes, eventually got real bad and couldn't rev over 3000 in 3rd gear! Multiple misfires down one side, lean/rich codes, read scare story's of timing being out etc. Took downpipe off and precat had completely collapsed and blocked. Best news ever! Definitely worth a look and gut them out anyway, removing piggys doesn't hurt and does release a little power, sounds better too.

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Ahh really. Sounds quite similar then. Like I’m at the early stages of what you described. Will get the downpipes off then and get them gutted. Glad the weather is better this week, think I’ll be under the car for a while!
Thanks for the reply!!