Hi, I have a 2007 hardtop S n14 engine with 120k miles. I've been getting alot smoke out of the exhaust after taking off from a stop light for a long time, and during hard acceleration. Also my front and rear main seals have been leaking as well. I replaced the front seal a few weeks ago so thats fixed. Anyway, I tried a piston ring soak with berryman b12 a week ago, soaked them for about 20 hours. This fixed my smokey exhaust AND it fixed my oil leak. I was surprised it fixed the oil leak, I guess air was getting drawn in from poor seals, then oil was getting pushed out. Now today, I'm smoking and leaking again. Can anyone tell me whats going on? The only thing I can think to try at this point is a new valve cover so the pcv gets replaced. I tried a new chinese valve cover a few months ago but that didn't help so I put the original back on. And by original this valve cover I put on around 80k miles. So it does have about 40k miles. I'm not sure exactly how many miles it has cause it was replaced a long time ago, I only drive about 4k miles a year.

 

Sounds like the valve stem seals are worn or hardening

 

When my N14 was having valve seal smoking issues, I used a bit of Lucas Oil Stop Leak and it reduces the smoke by a really good margin (until the next oil change). Only add a 1/3 of the bottle - I did this by adding a little every time I took the car out until it was around 1/3 of the bottle. If you add more than this you will end up having issues and codes, but in small amounts it does the job. It may also help with your RMS leak too.
You will eventually need to replace both the RMS and the Valve Seals in the future or the problem will end up getting worse.