I was recently having some vibration at idle issues in my 2011 Lariat. I changed the plugs and boots to no avail so I began checking for loose hoses from the engine. During my search I also noticed a lot of sludge built up on top of the drivers side wastegate and I was a little concerned. The passeneger side is completely clean. Any body have any idea if this is normal and what the issue could be if not? I’m sure this issue is most likely unrelated but my extended warranty ends in approximately two weeks. I’ve attached a picture for reference..... some of the sludge was wiped off by me while checking things out.