In alt.home.repair, on Sat, 28 Oct 2017 19:47:15 -0500, Paul in Houston
TX wrote:

micky wrote:
I have a 2005 Toyota Solara SLE, 133,000 miles, with P0171 and P0174
codes, lean mixture in both banks, and a check engine light that returns
soon after being cleared.

What are the O2 sensor(s) readings?
Can your scanner read or map the O2 voltages?
If not then use your dvm on the leads.
Check when HOT! 2k-3k rpm.

I think this is what you mean:

Equivalence Ration (lambda)(Bank 1-Sensor 1)1.065
Oxygen Sensor Voltage (Bank 1-Sensor 1)(V)3.573
Equivalence Ration (lambda)(Bank 2-Sensor 1)1.137
Oxygen Sensor Voltage (Bank 2-Sensor 1)(V)3.760
----------------------
Equivalence Ration (lambda)(Bank 1-Sensor 1)1.014
Oxygen Sensor Voltage (Bank 1-Sensor 1)(V)3.304
Equivalence Ration (lambda)(Bank 2-Sensor 1)0.949
Oxygen Sensor Voltage (Bank 2-Sensor 1)(V)2.980
----------------------
Equivalence Ration (lambda)(Bank 1-Sensor 1)0.982
Oxygen Sensor Voltage (Bank 1-Sensor 1)(V)3.160
Equivalence Ration (lambda)(Bank 2-Sensor 1)0.953
Oxygen Sensor Voltage (Bank 2-Sensor 1)(V)3.028
----------------------
Equivalence Ration (lambda)(Bank 1-Sensor 1)0.993
Oxygen Sensor Voltage (Bank 1-Sensor 1)(V)3.299
Equivalence Ration (lambda)(Bank 2-Sensor 1)1.010
Oxygen Sensor Voltage (Bank 2-Sensor 1)(V)3.307
----------------------
Equivalence Ration (lambda)(Bank 1-Sensor 1)0.992
Oxygen Sensor Voltage (Bank 1-Sensor 1)(V)3.300
Equivalence Ration (lambda)(Bank 2-Sensor 1)1.094
Oxygen Sensor Voltage (Bank 2-Sensor 1)(V)3.553
----------------------

So what they call voltages are more than zero and less than 12, and go
up and down around 3.1 to 3.6. So does that imply they are good?

I was going to take the connector apart and measure the resistance, but
it looked like I had to take off the air intake "funnel" first, and
then, it seems, the car started working right!