2000 Corolla, 45,000 mi, 1.8L

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JOSHER
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  • 17 POSTS
Car has trouble running first thing if it hasn't ran for a while. Check engine light has came on. Trouble code is P0171 (something like too lean left bank?) Please inform of most probable cause. Air filter is clean. Thank you, Sherri
Jul 23, 2007 at 12:14 PM
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RASMATAZ
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  • 75,988 POSTS
[quote:cb4ccd7860="josher"]Car has trouble running first thing if it hasn't ran for a while. Check engine light has came on. Trouble code is P0171 (something like too lean left bank?) Please inform of most probable cause. Air filter is clean. Thank you, Sherri[/quote:cb4ccd7860]

PO171 CAN BE CAUSED BY THE FOLLOWING:

A lean fuel condition can be caused by:

* Low fuel pressure due to a weak pump or leaky fuel pressure regulator. (use a fuel pressure gauge to check fuel pressure at idle)

* Dirty fuel injectors. (try cleaning the injectors)

* Vacuum leaks at the intake manifold, vacuum hose connections or throttle body. (Use a vacuum gauge to check for low intake vacuum)

* Leaky EGR valve. (Check operation of EGR valve)

* Leaky PCV Valve or hose. (Check valve and hose connections)

* Dirty or defective Mass Airflow Sensor (MAF). (Try cleaning the MAF sensor wires or filament with aerosol electronics cleaner. Do NOT use anything else to clean the sensor, and do not touch the sensor wires)

HTH/Good Luck!
Jul 23, 2007 at 1:17 PM
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