Question

My 2004 Volvo S60 2.4L will not pass inspection, a code came up P0171

Answer 1

P0171 Fuel trim lean Bank 1

Lean code are mostly when air or vacuum is unaccounted for by the MAF (mass air flow) there are several check that should be done, Sparkplug condition worn sparkplug where its gap is over specification tends to lean the fuel trim and can set a lean code condition, Emission hose that attaches to the MAF to the throttle body should be check,

 Oil cap or improperly sealing oil dipstick will set a P0171

 MAF air duct not properly  sealed will set a P0171, If all these area are good perform a MAF cleaning,

Answer 2

P0171 VOLVO - System Too Lean Bank 1

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