Left O2S Stays Below Center (Lean) (DTC 51)
NOTE:
For connector terminal ID, see CONNECTOR IDENTIFICATION. For wiring diagram, see WIRING DIAGRAMS - 3.5L
article in ENGINE PERFORMANCE. After each repair, perform TEST VER-2
.
NOTE:
Scan tool displays left oxygen sensor as O2 and right oxygen sensor as O2R.
- Using scan tool, set engine speed to 1500 RPM. Read left Oxygen Sensor (O2S) voltage. If left O2S voltage is always more than 0.5 volt, go to step 3). If left O2S voltage is always less than 0.5 volt, go to next step.
- If LEFT O2S STAYS BELOW CENTER (LEAN) trouble code is not in memory, replace restricted injector for left intake manifold bank. If LEFT O2S STAYS BELOW CENTER (LEAN) trouble code is in memory, a condition causing engine to run lean in all cylinders is indicated. Go to TEST NTC-1A .
- At this time, the condition required to set trouble code is not present. LEFT O2S STAYS BELOW CENTER (LEAN) trouble code sets if left O2S signal stays less than 0.5 volt without changing for more than 8 minutes. Possible causes are: major vacuum leak, low fuel pressure, other engine sensor calibrations, ignition system failure, left O2S failure, or fuel contamination. Go to TEST NTC-1A.