I've been putting off awhile replacing the spark plugs and PCV valve on my 2006 Sonata V6, I was planning on having the dealer do it. I ended up doing it myself. It took me about 3 hours to pull the intake off, learning from what I did it would only take me about 45-60 minutes should I do it again.
My Sonata has near 99,000 miles on it, has the original NGK factory plugs, I replaced them with Denso Iridium Power IK16 plugs. The PCV valve I bought at the Hyundai dealer.
The old spark plugs were in ok shape, they all had the electrode on there, the gap was good. The rear spark plugs were the best looking, the front spark plugs had some issues. A couple of the front spark plugs had traces of oil on them, and there was some deposits on them as well. The PCV valve was gummed out, it can only be replaced by pulling the intake, you can not see it with everything in the way.
My plan was to have the dealer replace all 6 spark plugs. Then I decided that I could do this myself and save some money. I did the front three first, and the plan was to let the dealer to the back. What was holding me back from doing the rear, all the wiring, hoses and not sure how the rear came off. After reading posts of people who claim to pull it off in 30 minutes, I hit it head on like a bull at a red flag and it took me about 3 hours to take off. Lots of guessing, looking, struggling with electrical connectors, hoses, then figuring out why the intake wont come off. The last things I did in removing the intake were removing the bolts that hold the bracket for the O2 sensor harness in the back and the fuel lines, then disconnecting the throttle body from the intake because I could not remove the electrical harness. I would have pulled the vaccum hose from the intake that leads to the brake booster but couldn't get the hose off, this was after the intake was removed.
The intake had residual oil on it. I dusted off the intake and rubber air housing hose they had dust/dirt in them.
IF you think you can't do it, my best advice is, just go out and tackle it, start disconnecting every bolt and harness, using process of elimination you will get that intake off. It looks complicated, it is to an extent. Putting everything back together is the easy part and you should be able to do that in 30 minutes. I didn't replace any gaskets they were all in good condition. Make sure you replace that PCV valve, this is the only time you will be able to access it.
I made a video and took some pics. I didn't video every single nut and bolt being removed, I did take some pics to see what it looks like with everything removed. The video just gives you a basic idea. http://www.youtube.com/watch?v=XlqRE3MD0oI
All comments welcome. What's the easiest way for you to remove those electrical connectors? They all seem to differ, some you push and release on the side, others have tabs, pain in the rear.