DTC P0171 = System Too Lean (Bank 1) - the TT service CD says check: fuel pump, fuel filter, pressure regulator, MAF, and vacuum leaks.
My 2002 TT 1.8 Quattro w/ an AMU engine runs fine, so fuel delivery seems unlikely. This code came up at the same time my Secondary Air Injection motor failed from exposure through a broken hose. New motor and new hose are on. DTC # p0171 remains.
I am going to search for a vacuum leak before considering the MAF and the pressure regulator.
Has anyone trouble shot this problem before? I assume the cluster of vacuum hoses on the SAI assembly near the intake manifold is a good place to start. Are there other places I should inspect that are prone to leaks? Does this approach seem reasonable or am I missing something?