Toyota 4Runner Forum - Largest 4Runner Forum - Faulty cat and EGR system

I just happened upon this thread on Tacoma world, a guy stripped his whole engine down to chase a 'sparkly oil' fault. It turns out, well read his words rather than mine:

Quote:

I head to the garage with coffee in hand. I start looking over everything again looking for a sign.
I pulled the VVT screens. They both look free of debris. (Sorry no pics)
I was thinking to myself, maybe out loud, "what in the hell, why can I not find a cause of failure." This is kinda going over and over in my head, along with "everything looks real damn good".
The thought enters my head, "the only time I have seen oil that bad and the engine not blown up was when a catalytic converter failed." My immediate next thought, almost before the first was finished. "NAHHHHH, I just put new high flow cats on when I did the shorty headers, less than a year ago." As I turn to look at the cats, "well **** it, I can't think of anything else so why not." I look at the bottom of the cat, looks ok. I walk over and grab a bite scope and I start feeding it down the exhaust runner and I start twisting it a round looking at the monolith. The fist one looks good. Move on to the second one. Bottom looks good. Slide the scope down to look at the top. As I'm rotating the camera around I see something.....off. I start repositioning the camera and I see it. Well, what's not there.

Well, this has turned out to be $3500 mis diag. Well, I can't say misdiagnosed. I just caught it before she went nuclear.
With all that cat dust in there it would have acted like a super fine grinding paste. It would have continued to get worse and worse.
A little info for those that may not understand how that could get into the oil.
The trucks do not have EGR, why? That function is incorporated in to the VVT strategy and cam timing. It will draw a little exhaust back into the engine through the valves instead of pumping it into the intake like a traditional EGR.
As the exhaust is drawn back into the cylinder it brings the catalytic converter dust with it. From there the normal blow by and sticking to the oil cylinder walls to be scraped off.

1GR-FE rebuild | Page 7 | Tacoma World

I've been tinkering with and reading about cars/bikes/engines for 20 years and I've never heard of anything like this!

Just posting as it might help someone, somewhere, one day...