Fuse diagram avalon 2009 xls

SOURCE: check engine light on;engine codes p0420 and p0773

I looked up the codes you posted.
P0420 is showing a bad oxygen sensor on bank #1, the one down by the catalytic converter.
P0773 is an electrical problem with the shift solenoid E.
A bad oxygen sensor would cause lower fuel milage.

SOURCE: P0171 check engine code on 2000 Toyota Avalon XLS

more than likely your mass air flow sensor is bad. it is located. on the air fliter box to the right of the box lid. cost about $200.00 at the dealership. go to autozone or advance and you can the same thing this one is a refurbished one for half to cost. un plug sensor. un screw two phillips screws, pull it out and put the new one in. thats it. good luck

SOURCE: My 2004 Toyota Avalon XLS will not start. The

The first thing to do is try another key. Perhaps your transponder key has failed.
You can identify a 'transponder key'; it has a wide part wher you turn it.

SOURCE: concern with the timing belt 1997 toyota avalon xls

The maintenance interval is 60,000 miles, but they usally last quite a bit longer before they fail.
This is a non-interference motor , meaning the valves will not hit the pistons if the belt brakes.

SOURCE: The check engine light produced codes p1150 and

All cars sold in the US after 1995 use the same on board diagnotics called OBD-II. The codes are the same. Search OBM-II error codes and you'll get a listing.

P1150 Air/Fuel Sensor Circuit Range/Performance. (cylinder bank 1 Sensor 2)

P1150 may mean that one or more of the following has happened:
water or corrosion in the O2 sensor connector, loose terminals in the connector, wiring burnt on exhaust components, open or short in the wiring due to rubbing on engine components, holes in exhaust allowing unmetered oxygen into exhaust system, unmetered vacuum leak at the engine, bad O2 sensor or bad PCM.

P1155 Air/Fuel Sensor Heater Circuit. (cylinder bank 1 Sensor 2)
P1155 may mean that one or more of the following has happened: O2 Heater element resistance is high, Internal short or open in the heater element or O2 heater circuit wiring high resistance

Solution :Replace oxygen sensor and see if the problem goes away.

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