[Tigerguy]

Hi, everyone. I'm a first-time poster from Houston. I've not owned a Subaru before, but I'm very interested in the Ascent. But, does anyone know the technology used by Subaru to prevent carbon build-up on the intake valves? For example, Toyota adds port fuel injection to spray, intermittently, fuel on the outside of the valves. Mazda uses valve timing to ensure that the metal in the valves gets hot enough to burn off the carbon. Thanks for reading!

Tigerguy

 

[Robert.Mauro]

Hi, everyone. I'm a first-time poster from Houston. I've not owned a Subaru before, but I'm very interested in the Ascent. But, does anyone know the technology used by Subaru to prevent carbon build-up on the intake valves? For example, Toyota adds port fuel injection to spray, intermittently, fuel on the outside of the valves. Mazda uses valve timing to ensure that the metal in the valves gets hot enough to burn off the carbon. Thanks for reading!

Tigerguy

Hi!

You'll find this thread starts talking about it. From what I can glean across multiple forums, no manufacturer has quite mastered it, though there are some methods of mitigating it somewhat.

LINK:

• http://www.ascentforums.com/forum/10-engine-technical-discussion/803-all-new-2-4l-turbo-subaru-engine-ascent-9.html

 

[Trey T]

Perhaps upgrade the crank ventilation component to something aftermarket (better OAS)? Racers use catch-can to retrieve the oil from the crank