what to do if im getting Engine code po171 on my 2006 Chevy trailblazer v6?

Question

I have cleaned the MAF (Mass air flow) sensor and the throttle body and replace downstream and upstream 02 sensors and clean pcv hose and replace the air filter and sparkplugs and gas cap and no leaks in the intake system even put injector cleaner liquid and ran the car but keep getting engine code po171 too lean bank 1.

Answer 1

Still have the problem?try this...

Test for fuel contamination,small amounts of water can be delivered to fuel injectors and cause a lean exhaust  indication.A lean exhaust indication can be caused  by too much alcohol in the fuel.The system go lean if an injector is not supplying enough fuel.A lean condition could be  present during high fuel demand  due  to a fuel pump that does not pump enough fuel.

Put pressure gage on fuel rail, switch on but do not start,observe fuel pressure,after pump stops pressure should stabilize and remain constant at 50 to 57 psi ,if pressure drops  possible causes  fuel pressure regulator, leak from fuel  hose inside tank or fuel pump.

Hope this will help.............