Anyone ever attempt (with success) cleaning the matrix of a catalytic convertor ? Are there any solvents which are proven to be safe to use to dissolve and remove oil, combustion, etc. residues without damaging the matrix material or its various coatings ? Can the convertor be soaked or flushed ? --- off the car, obviously.
Some makes have that problem, usually from long term oil burning. The only thing I have heard of is to restore proper running and get them hot to burn it out. If they are dead I don't suppose other methods aren't worth a try.
I just googled it for poops and giggles, they wash them out with soap and water to get rid of oil deposits Band aid on a broken bone. Got to love the internet
The ones I saw on the Benz's was hard and caked on much like a caked on oil deposit on a plug electrode but at lease we know soap isn't a problem.
Maybe drop them in a kiln for a nice slow controlled burn to clean them out good and proper just below the burn of the stainless steel. We have some serious kilns at the shop I would give it a try next bad one I can get. Or put an afterburner on those cats to clean them from those short distance stop and go drivers LOL
Thanks for the advice guys. This a turbo-charged Audi that failed an oil seal on the turbocharger, so the cat has quite a bit of oil residue blown into it --- but it is not plugged up --- so I thought I might try to salvage it. I'm getting a lot of A/F mixture-related codes due to the contamination affecting the cat's ability to do its job and causing the O2 sensors to be sending some really screwy signals. Which brings me to another question ---- Is it possible to clean a contaminated O2 sensor ? Or should I just toss them and get new without even trying to fuss with it ?
Yeah take it for a long spin heat that cat up good and proper then maybe replace the 02, they are cheap these days Erick good one LOL
LOL --- technically..... that is cleaning a Cat *externally*. To clean one internally, could be messy....... think *kitty enema*
Given the construction and the porous ceramic structure once fouled they are hard to get cleaned enough to where response time and counts per event are accurate enough to be useful. If your up for the reading read up on O2 sensors, given your technical background it will answer a lot of questions you may have. the wiki page is good.
My two cents: A new O2 sensor is a lot cheaper than repairing the damage that can be caused by long-term operation with a bad air-fuel ratio.
. Makes sense but I actually have cleaned a cat with soap and water on a car that was close on smog. All kinds of yuk comes out but certainly not all of it. Then blowing compressed air/water as in pressure washer in backwards also moves stuff out. That might be enough to free up enough cells of the cat so that it works well enough to get hot enough to burn the rest of the junk off the cat. I don't know the real mechanism of action but it worked and the car passed smog. When you are a home mechanic, not on the clock, you can try stupid stuff like this and sometimes you get lucky. I don't know the long-term benefit because the car was sold a year later.
Don't misunderstand --- I'm not looking for ways to save a few bucks or do this on the cheap. I'm just wishing not to consume parts if they are not necessarily consumables (in this particular case). The sensors have not failed --- they are just dirty. But, if they can't be cleaned, they are as good as failed of course. I'm much more concerned about recovering / cleaning the Cat ---- that is not a part to simply toss out just because one doesn't want to spend a couple of hours cleaning it up.
oh, I was referring to the O2 sensor not the catalytic convertors. For the catalytic convertors, usually getting them up to temp can burn off most contaminants, pre cleaning with a degreaser and hot water may help. I'd be more concerned with solvents or anything that contains hydrocarbon chains and the list of known contaminants that react with the catalyst agent or remove the wash coat that binds it to the substrate. Without a kiln to reach the high temps needed to 'burn' off the gunk that means doing it with engine running, might be a problem for the ECU though. Unless you've got funky mfg only specific fitment, aftermarket cats are reasonably cost effective to just replace with new, at least finnerty is not in CA where this is more of a PITA!
