Saw something wild at the salvage yard in Tacoma last week

I was pulling a transmission and noticed at least five cars from the last two years with the same engine failure. All of them were direct injection four cylinders with serious carbon buildup on the intake valves already. Has anyone else seen this becoming a regular thing on newer models?

4 comments

4 Comments

reesej272mo agoMost Upvoted

Tried a catch can setup on my own car to see if it would help. It actually caught a surprising amount of oil vapor from the PCV line before it could reach the intake. The valves looked a lot cleaner at 40k when I finally checked them.

quinn_reed172mo ago

Spotted the same thing on a few low-mileage lease returns. My wallet hurts just thinking about the walnut blasting bill.

sethfoster2d ago

reesej27 mentioned the catch can actually catching oil vapor, but heres the thing nobody talks about - those catch cans are just a bandaid for a bigger problem. The real issue is how these manufacturers keep cranking up the oil change intervals to like 10k or 15k miles. That old sludgey oil breaks down and makes way more vapor than it should. Ive seen engines that got changed every 3k miles with conventional oil have way less buildup than the ones running full synthetic for 10k. Its like the oil itself is part of the problem before it even hits the valves.

the_paul2mo ago

Wasn't there a big forum thread about this on the VW boards? I remember reading that some of these newer turbo engines, especially the ones without port injection to wash the valves, are getting coked up crazy fast, like by 30k miles. The oil vapor from the PCV system just bakes onto the hot intake valves.