OK..Here we go again. P0171 is reporting lean fuel mixture on Bank 1. New plugs, wires, MAS and Oxygen sensor have been replaced. After clearing error codes, P0171 appears after a few miles. I then purchased Seafoam and sprayed anout 1/3 of the can into the throttle body, the rest into the tank. Still no resolution. Presuming some injectors are clogged/dirty, what is the best (and cheapest) method of cleaning the injectors? Any ideas on service places to use and guesstimetes of prices..?