Hello everybody,

I've tried to do some research and need some help..

I am pulling these codes (P0171 P0174) on a 2001 E250 4.2 V6. I am assuming a vacuum leak but cannot find the darn thing. I think there is a leak because with the hood open and engine running, I can feel a lot of air blowing out from the passenger side. Where would the hoses I need to be looking for located?

Also, I saw on the passenger side, there are 2 pretty thick hoses connected to something one on top of another and I saw that the lower one has some sort of mesh heat shield wrapped on a part of it, possible repair from the past? I don't know. But when I unplugged it, oil was spilling out so I don't think air was coming from there although it seems to have been patched up previously.

Any insight would be greatly appreciated.

Regards.