Originally Posted by Falcon_LS
I would skip the Seafoam, it's not going to do much for your situation.
Three important things to check first:
You have a vacuum hose that runs from the block directly to the intake manifold on the driver's side of the engine, to the right of the PCM. Pull that hose off and make absolutely sure it is not blocked. If it is, I suggest you get some Simple Green Industrial Cleaner and Degreaser, pour some into bucket undiluted, enough to cover the hose, and let it sit overnight.
Next, pull the intake resonator off and check to see if there is a strong vacuum from the nipple behind the oil fill cap on the valve cover at idle. It should make a whistling sound with the hose not connected.
Finally, although you may not have a check engine light, check to see there are no codes stored in the PCM, particularly a P0014.
A couple of notes; this engine has a reverse flow cooling system with variable valve timing on the exhaust side, allowing for 25º of cam phasing, which eliminated the need for an EGR system. While this setup allows for a 25% reduction in hydrocarbons and a 40% reduction in nitrogen oxide, the engine runs hot. If you have any issues with the camshaft actuator, triggering a P0014, this will throw the system off course.
Although others may choose to disagree, I think it is especially important to run a relatively low NOACK (span>10%) oil in this application. Over the 130,000 km of my ownership running an MB Sheet 229.5 approved oil with span>10% NOACK, I have never had any issues with the PCV system. The area surrounding the vacuum nipple on the valve cover and the resonator is bone dry on mine with 210,000 km on the clock. I follow the OLM with a simple drain/refill of 6 liters at the 50% mark (usually 7,500 - 8,000 km) and a filter replacement once I'm under 1%. I have never had to add any oil, either during the first 7,500 - 8,000 km phase before the drain/refill, or after. When you switch to a different oil, you may initially have oil consumption for the first two oil changes before it normalizes.
does the nipple/valve connecting to the intake resonator with the "PCV" hose supposed to have vacuum though?
i thought it's just a valve on the valve cover that blow by gases goes up and back into the intake through the throttle body, or do I have this reversed in that vacuum sucks air in, mixes with the blow by and then it goes out through the exhaust manifold?
thanks again for the help.