98 passat code 1136 and 0303

I have a 98 Passat w/1.8 turbo, gas burner. We got this for my mother a couple of months ago. It has been running fine with no problems until today. She called and said it was cutting out and the c/e light was on. I took the car to Autozone and pulled the codes myself. I found a code P1136, Manufacture Control fuel/air metering and a P0303, #3 cylinder misfire. It definitely has a skip/miss to it and I was checking everything under the hood and on the l/f corner (just left of the engine) there is a plastic cover that covers up some vacuum lines. One of the lines y's off and has a check valve in it. It looks like someone has "repaired" the valve previously with glue but now it has come completely into. There is defiantly a leak there, My questions are this, What is the check valve called, is it a dealer only item? Also will the vacuum leak like this cause the P0303 cyl misfire code. I have pictures of the check valve if further explanation is needed.

Thanks,
VSA
Romans 8:28

The parts are best bought from the dealer, I don't know the name. Call dealer and ask for the part and price.