[kb3gup]

Hey guys. Along with everything else I decided to borescope a few cylinders today, my mother was having surgery so I only got 2 done before I had to be back at the hospital. #1 was up and hard to see with the camera but with a flashlight it looked pretty good, small amount of carbon on top. But #5 is a different story?? Keep in mind I'm having rich running long term fuel trims on both banks and I have no idea how long it's been going on for. I almost always use top tier gas, and 93 octane or I get KR. I also use chevron with Techron occasionally. What do you guys think? And what are those swirls? Sorry for the quality my borescope is a real cheap one. https://youtu.be/XpAi_dXNVGk

Thanks!!!

 

[kb3gup]

I've tried every sort of induction service to get rid of the carbon with limited results, including the professional BG with the professional machine. I'm now looking at using seafoam through a vacuum line. I know there's a safe way to do it using a smaller diameter hose and dipping the hose into the seafoam and letting the engine "sip" it. However in all the articles I've read they've said don't let the seafoam go through brake check valves. That's kinda hard on these cars, the last check valve (assuming that's what they are) is only 2 inches from where the hose goes into the engine. My auestions are:

1. Why, what would it hurt?
2. 2 years ago I already did it, when I poured about half a can through, with no problems, except these high fuel trims, could I have damaged something in that check valve that's causing this?

I'm able to sit at idle and pump the brakes and make the fuel trims max out (positive numbers). I'm told this indicates an internal vacuum leak. Could it be one of those check valves that was damaged from the seafoam? Thanks!