Greetings pkufeldt,
Welcome to the GMT400 forum! Don't know if you've lurked prior to
posting, but Schurkey is a Subject Matter Expert, and you are in
good hands.
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Listen, the fact that you are A) already capturing data, and B) are having
issues with your long-suffering cats, you may be in a position to
factually prove/disprove what I've heard from several people that
I trust. (But I haven't had the need to try this 1st-hand?)
What I propose is that you try a catalytic converter cleaner that
several mechanics around here swear by in order to get a car
past the annual NY emissions test. (CEL lit, P0420 code, etc)
After trying said 'fix in a bottle', do your data capture, upload to
here, and then we can compare your original data vs. post 'cat clean'.
If there's no change, then we know. If there is a change, then we
can quantify the improvement & file that away for future reference?
Here's the magic juice that (supposedly) gets your tired ride another
sticker for another year:
You must be registered for see images attach
Here's the Amazon link: (
link)
I read through a few of the customer reviews, and in general they sound
similar to what the mechanics told me. Big picture, this bottle won't
repair a bad wiring harness down to an O2 sensor, or unmelt a cat
where the honeycomb has been Chernobyl'd. And a few of the reviews
are wondering if the fact that the power windows quit working shortly
after using the cataclean is the fault of the product? :0)
Seriously, I'm trying to separate the troubleshooting wheat from the chaff,
and you might be a perfect candidate to do just that.
As for whether this actually works on not? In the second review down
a gentleman (possibly with a chemistry background) said that this
product generates Carboxylic Acid, which acts as a solvent to
remove the surface layer of crud & baring the underlying platinum
to the passing exhaust gas, allowing the catalyst function to restart?
****
As I mentioned above, I haven't had a P0420/30 code to work on since
this stuff showed up on the parts store shelves, but if the opportunity
presented itself I would do all the standard revival stuff first, then the
'cat cleaner'. (Fresh plugs, oil change, air filter if needed, Italian tuneup,
go to emissions testing with the warm afterglow still on.) I would add
the 'cat cleaner' between air filter & Italian tuneup?
Again, I initially dismissed this product as the usual 'engine rebuild in a
can' hokum...but I had a few people I trust tell me that it actually
makes a difference -- to the point that they won't spend the customer's
$,$$$ on cat replacements until they try this first?
Bottom line, I'm on the fence about this stuff, but with your data logging,
and assuming that your cats would still pass a visual inspection, then
maybe this stuff can remove enough of the surface contamination
(from the recent misfiring) ...that it will show up in your data logs?
And possibly even clear that P0430?
Or, maybe the cat clean + replacing a lazy upstream O2 sensor will
give the computer what it wants to see?
Whatever happens, best of luck finishing the fix!