P0174 BMW -

Question

2005 BMW 325I COD PO174 171 WHAT IS THE PROBLEM WHAT NEEDS TO BE REPLACE

Answer 1

P0171 Fuel system lean Bank 1

P0174 Fuel system lean Bank 2

Most causes of lean bank system are the air intake duct of the MAF (mass air flow) sensor  that is not properly seated. That or the MAF itself. Improper sparkplug type can also cause these code condition.If there is no vacuum causing false air the PCV  system has to be looked at. If there is strong manifold vacuum when you pull the oil dipstick out (during engine running) the oil seperator system will be the cause for this condition.