P0171 Code Toyota Corolla 2006


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MODEL:Corolla CE 5-spd Manual
YEAR: 2006
MILES: 104000
DESCRIBE ISSUE.... CEL came on today and Code is P0171. Bank 1 Too Lean. Code showed in both Logged and Pending. SFT1 fluctuates between +4 and -4 in Neutral. My BAFX OBD interface and Torque Lite don't display values for O2 sensor voltages Bank 1 Sensor 1 or Bank 1 Sensor 2. Simply "No Data."

This car's had no work done but Air Filter Replacement, Oil/Filter Changes, and New Front Brake Pads. It's due/overdue for Plugs and Wires, and I wouldn't object to replacing both O2 Sensors.

But I'd really appreciate your counsel before I just jump in and throw parts at it, even if they're due.

Also have NOT cleaned Throttle Body. Should I?

I cleared the Code, so we'll see how long it takes to come back. THANKS!!!


Hero Member
Here's a non-update... When I pulled codes I did a re-set, and it hasn't been back. I'll check the ducting for connection and damage, but things have come up that have kept me from doing it as promptly as I planned. I'll still do it.
Happy Friday!


Hero Member
Just an update. Code has NOT returned, and inspection of the duct between Air Filter and Throttle Body (corrugated like a vacuum cleaner hose) appears intact. Its clamps are also tight.