engine light on /oxygen sensors on 2006 Toyota Corolla

how many oxygen sensors does this car have...and where are they located? are they also called mass. airflow sensors?....I had an oxygen sensor replaced a few weeks ago, my engine light was on.....now the light is on again, took the car to a differant garage ,had it coded.. says its the sensor again... did I get taken by the toyota garage....cost me 315.00 the first time, I dont want to go back there!!!!!

by in Queensbury, NY on April 06, 2011
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1 answer
ANSWER by , April 06, 2011
first of all, i would return to the first shop to ask them to check there work and see if it is the same code. they should not charge you anything for this service as they just did a diag and repair. when they call you and tell you the issue, get a bid in writing and check with another shop for a second opinion. we have, at times, replaced sensors that were defective right out of the box. give them a chance to check there work before condemning them. thanks for using repairpal Roy