Sounds like you found the problem Here's a list of other problems that can set off po171 code- vacuumhoses for splits, kinks impropper connect-Insufficient fuel in tank,low fuel pressure, malfunctioning fuel injectors,vaccum leaks at intake manifold,throttle body and injector O rings, air induction system and the intake ducts for leaks or a missing air filter. A cracked EVAP canister,Evaporation pipe obstructed or leaking,crankcase ventalation system leaks, HO2S electrical wires contacting exhaust/shorted /grounded to low reference circiut or a malfunctioning engine. Off the top of my head thats all I can think of that sets off codePO171 Special thanks to the GM service manual 2008M-car for Solstice/Sky for there input into my brain darn just got a brain malfunction light help! Now a bladder full light,methane alarm #@^@^
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