Toyota Corolla (E120): System too lean/rich

Dtc p0171 system too lean (bank 1)

Dtc p0172 system too rich (bank 1)

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Starting system
Inspection 1. Inspect starter assy Notice: these tests must be performed within 3 to 5 seconds to prevent burnout of the coil.  perform the pull–in test.  Remove the nut, then disconnect the lead wire from terminal c. Connect the battery to the starter repai ...

Circuit description
In the diagram below, when the engine is cranked, current flows from terminal st2 of the ignition switch to the starter relay coil and also current flows to terminal sta of the ecm (sta signal). When the sta signal and ne signal are input to the ecm, tr is turned on, current flows to the c ...

Sound quality is bad only when playing tape
Inspection procedure 1 Replace cassette tape with another and recheck Replace the cassette tape with another and recheck.  Replace the faulty cassette tape with the normal one to see if the same trouble occurs again. Standard: malfunction disappear. 2 Check for any foreig ...