You might want to do that.
I pulled the intake manifold a couple of weeks ago to replace the glowplugs and noticed the intake ports and valves were filthy. I didn't have time to clean them so 2 weeks later the manifold came off again for cleaning. I used a couple of picks from HF but by far the best tool was a butter knife with the tip bent over 90 degrees to scrape out the grease. After scraping out as much as I could, I used some carb cleaned and a vacuum attached to a 1/4" hose to suck out the greasy liquid from the intake valves. I went through a large pack of paper towels and scraped out enough grease to make a couple of golf balls. The EGR was blocked off a year ago and crankcase vent has a catch can but I guess thats not enough to make the existing deposits magically disappear. Since cleaning it out the engine seems to build boost a lot quicker with less WOT smoke. I'm happy. I'm not sure about power since only had a chance to drive the car loaded.