I have a 02 MPV throwing lots of lean fuel codes. I have spent $600 this month and nothing seems to fix it.The first set of codes were for a lean fuel mix so they replaced some parts (cant find the paper work with codes and what was done). Then about 10 miles down the road the engine light came on. So took it back to the shop they said that codes P0171,P0174 came up and the suggested fix was pcv valve and new intake gaskets. Ok so I did that then about 10 miles down the road the engine light came on again. Called the shop told them what happened. I took it in now they say that code P0174 came up lean fuel mix suggested fix now is o2 sensor. They said the o2 sensor was reading .85 which is .10 higher than it should? I declined repairs cause they wont guarentee that this will fix the problem. I asked how I can spend $600 dollars and still have the same problem. There reply was that you fix the vehicle in a suggested sequence to "repair" based on how the car is acting. Am i geeting screwed or is this common for chasing codes. I have heard this year 02 MPV was the wosrt year for this vehicle. I have spent about $5000 in the past year on repairs PLEASE HELP