I HAVE A 171 AND A 174 CODE ON A 2003 TOYOTOA SOLARIA V6
on 2003 Toyota Solara

I HAVE CEL FOR A P0174 AND P0171 ON A 2003 TOYOTA SOLARIA V6 AT IDLE CHANGE MASS AIR FLOW SENSOR CEL STAYED OFF FOR TWO WEEKS THEN CAME ON AGAIN

Asked by for the 2003 Toyota Solara
2 answers
http://www.obd-codes.com/p0174
http://www.obd-codes.com/p0171
Both are lean codes my guess would have been the MAF sensor. Next I would look at fuel trim data on a scan tool to see how out of range it is , I would look at the O2 sensors and look at fuel pressure and fuel delivery. I would suspect a vacuum leak or defective MAF sensor.
Hello yes these are lean fault codes and you should check for vac.leaks after the mass air flow sensor possibly the air intake duct may be torn in the seams or there may be a intake manifold gasket leaking and as Hal stated there may be a fuel pressure issue or faulty O2 sensor.HAVE A BLESS DAY from DR.RECO.