2002 Toyota Sienna 6 cyl Front Wheel Drive Automatic 171500 miles
I failed my emmisions test. The error code reads P0420: catalyst system efficiency below threshold (bank 1). I have been told this is o2 sensor behind manifold near firewall and that the old ecm should be replaced with a new one because this was a problem the ecm's had that toyota fixed. What say you?
have the same problem?
Tuesday, February 17th, 2009 AT 11:53 AM