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2002 Toyota Corolla Question: toyota corolla 2002 code p0171
bmdouble January 28, 2013, 15:11Master
po171-bank 1 system lean.Start by checking for vacuum leaks.Don't fall for the oxygen sensor diagnosis that many parts stores have told many of my customers.9 times out of 10 it is a vacuum leak.
Answer #2cntsmith January 29, 2013, 05:09Enthusiast
in agreement w/ bmdouble as most likely-will add contaminated maf sensor/restricted fuel filter as other possibilities if no vacuum leaks are found.