My check engine light is on.  My ³not a dealer² mechanic says that
the code(s) that he reads define one of two possible repairs bith
pricey.  He suggested that I see a dealer so that if the dealer guesses
wrong I will be pissed off at the dealer and not him.

    I went to AutoZone and read the codes.  Their ³meter² says that 4
codes are involved but when I get the numbers two of them repeat.  The
codes that come back are:

    P0171  System too lean (Bank 1)
    P0174  System too lean (Bank 2)
    P0171  System too lean (Bank 1)
    P0174  System too lean (Bank 2)

    Responses to posts on this code suggest replacing the O2 sensor.
One respondent questions whether both would go out at the same time.  

    I guess the next question is whether I should replace both of the
pre catalytic converter sensors first or the post catalyåtic converter
sensor first.

    The dealer quoted $225 each for the pre coverter sensors and 128.80
for the post converter sensor plus $166 labor if all three are needed.

    After market pre catalytic sensors sell for $78.81 at Autozone,
post converter sensors are special order

    I am just outside the 5 year emissions warrenty period but only
have 46K miles.  Anyone know of a special warrenty extension.

    Note that I have an 01 Sienna with a V6 engine which I believe is
the same engine that is in the Camry V6 (there is no Sienna newsgroup).    
My check engine light is on.  My ³not a dealer² mechanic says that the
code(s) that he reads define one of two possible repairs bith pricey.  
He suggested that I see a dealer so that if the dealer guesses wrong I
will be pissed off at the dealer and not him.

    I went to AutoZone and read the codes.  Their ³meter² says that 4
codes are involved but when I get the numbers two of them repeat.  The
codes that come back are:

    P0171  System too lean (Bank 1)
    P0174  System too lean (Bank 2)
    P0171  System too lean (Bank 1)
    P0174  System too lean (Bank 2)

    Responses to posts on this code suggest replacing the O2 sensor.
One respondent questions whether both would go out at the same time.  

    I guess the next question is whether I should replace both of the
pre catalytic converter sensors first or the post catalyåtic converter
sensor first.

    The dealer quoted $225 each for the pre coverter sensors and 128.80
for the post converter sensor plus $166 labor if all three are needed.

    After market pre catalytic sensors sell for $78.81 at Autozone,
post converter sensors are special order

    I am just outside the 5 year emissions warrenty period but only
have 46K miles.  Anyone know of a special warrenty extension.

    Note that I have an 01 Sienna with a V6 engine which I believe is
the same engine that is in the Camry V6 (there is no Sienna newsgroup).