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Test TC-9A - O2S Stays Above Center (Rich) (DTC 52)

WARNING: This page is about a different car, the 1995 Dodge Ram Wagon, 1995 Dodge Ram Van, 1995 Dodge Pickup, and 1995 Dodge Dakota. However, it is still accessible from the selected car via links, so may be relevant.
  1. Start engine and apply parking brake. Using scan tool, set engine speed to 1500 RPM. Using scan tool, read Oxygen Sensor (O2S) voltage. If O2S voltage is less than .5 volt, condition required to set DTC is not present at this time. Go to next step.
  2. O2S STAYS ABOVE CENTER (RICH) DTC sets if O2S signal stays more than .5 volt, but less than 1.2 volts, without changing for more than 8 minutes. Possible causes are high fuel pressure, other engine sensor calibrations, failed ignition system, failed sensor, and fuel contamination. Go to TEST NTC-1A.
  3. If O2S voltage is more than .5 volt, check for tracking from O2S connector, 12-volt ignition feed (heater) circuit (Dark Green/Orange wire) to O2S signal circuit (Black/Dark Green wire). Go to next step.
  4. Check O2S connectors for excessive dirt and grease build-up. If there is excessive dirt and grease build-up, clean and repair connector(s) as necessary. Perform TEST VER-2. If no excessive dirt or grease build-up is present, a condition causing engine to run rich is indicated. Go to TEST NTC-1A.
  5. If voltage is not always more than .5 volt, condition required to set DTC is not present at this time. Go to next step. If voltage is always more than .5 volt, go to step 7).
  6. 02S STAYS ABOVE CENTER (RICH) DTC sets if O2S output voltage stays at more than .5 volt, but less than 1.2 volts, without changing for more than 8 minutes. Possible causes are: high fuel pressure, other engine sensor calibration failures, ignition system failure, O2S failure or fuel contamination. Go to TEST NTC-1A.
  7. Using scan tool, stop all actuation tests. Turn ignition off. Inspect air cleaner filter and inlet ducts for restrictions. If restrictions are present, repair as necessary. Perform TEST VER-2. If restrictions are not present, remove upper half of intake manifold.
  8. Turn ignition on. Using scan tool, actuate Auto Shutdown (ASD) fuel system test. Inspect all injectors for leakage. If injectors are leaking, stop ASD fuel system test. Release fuel pressure. Replace leaking fuel injectors as necessary. Perform TEST VER-2.
  9. If injectors are not leaking, using scan tool, stop ASD fuel system test. A condition causing engine to run rich is present. Go to step 6).
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