Hello everyone. I took my 2008 Pontiac GP 3800 to a GM service dept to have the P0106 and P0420 codes checked out and they claim I need a MAP sensor $93.00, Map sensor system cleaning $200.94, a EGR system cleaning $200.94 and a Fuel injector cleaning $139.00 which will cost over $700 bucks! I think they are trying to pull one over on me. Has anyone ever had problems with these codes?? Please let me know what you think... Your help would be most appreciated...