So, as you guys probably already know, I own a 2010 VW Jetta Wolfsburg Edition. I have a love hate relationship with it. It runs good when it runs….It drives nice and is comfortable. I haven’t had anything wrong with it that I couldn’t fix but it has had way more issues than my Honda did. Of course, my Honda was not turbocharged and didn’t have heated seats or leather for that matter. I ended up just calling this car high maintenance.
I recently did the fuel injector seals (again!) on this car and noticed that the intake valves were caked in carbon. It was disgusting! I have been listening to the motor medics (props to them, I have learned so much just listening on my way home from work) and know that the GDI motors tend to get this build up since the fuel is not cleaning the intake tract and is instead being directly injected into the combustion chamber. I thought that I was fine since they state if the car gets good heat cycles that I shouldn’t have a problem since the heat will help keep the build up to a minimum. Since my commute to work is over 50 miles each way I thought I should be good.
I did not experience any drivability issues because of it but when I took the Intake manifold off the head I noticed that my intake valves were caked in carbon. Some symptoms of needing to do this would be cold start misfires, random misfire codes (this can also be due to crappy coil packs), and a decrease in gas mileage. Since I had the intake manifold off, I decided to clean them to the best of my ability. Not sure if this is the recommended procedure but it seems to have worked for me.
I sprayed the valves with throttle body cleaner, I’ve also heard good things about sea foam but that seems like more of a maintenance item, and went to town with a flat head screwdriver. Writing that down, it seems that this might not be the best way to do this, but this is the way I did it and it worked! The first time around, I attempted to use a wire brush but it was not as effective as the screwdriver. I was very careful not to damage the valves while still scraping the carbon off of them. This took some patience but in the end you could see the valves again.
I also cleaned the baffles that are inserted in the intake tracts in the head. They were also full of carbon buildup. Some throttle body cleaner and a rag resolved that issue. They were pretty clean when I put them back in.
As I said, I was doing the fuel injector seals due to one of them leaking like a sieve and decided that it would be a good time to clean the intake valves. You can follow the instructions in this post to remove the intake manifold and then just clean the intake valves.