DTC P2096, P2097

DTC P2096  : Post Catalyst Fuel Trim System Too Lean

DTC P2097  : Post Catalyst Fuel Trim System Too Rich

NOTE: 

• Before you troubleshoot, review the general troubleshooting information .
• If any of the DTCs listed below are stored at the same time as DTC P2096 and/or P2097, troubleshoot those DTCs first, then recheck for P2096 or P2097.

  P0130, P0133, P2237, P2238, P2243, P2245, P2251, P2252, P2A00: A/F sensor (Sensor 1)

  P0134, P0135: A/F sensor (Sensor 1) heater

  P0137, P0138, P0139, P2270, P2A01: Secondary HO2S (Sensor 2)

  P0141: Secondary HO2S (Sensor 2) heater

  P0171, P0172: Fuel system

  P0201, P0202, P0203, P0204: No. 1-No. 4 cylinder injector(s)

  P0300: Random misfire

  P0301, P0302, P0303, P0304: No. 1-No. 4 cylinder misfire

  P0351, P0352, P0353, P0354: No. 1-No. 4 cylinder ignition coil(s)

DTC (PGM-FI)

1. Problem verification

   -1. Turn the vehicle to the ON mode.

   -2. Clear the DTC with the HDS.

   -3. Enter the maintenance mode, then start the engine .

   -4. Hold the engine speed at 3, 000 rpm without load (in P or N) until the radiator fan comes on, then let it idle.

   Test-drive the vehicle under these conditions:

   • ECT Sensor 1 above 158 deg.F (70 deg.C)
   • Transmission in D
   • Engine speed below 4, 000 rpm
   • Drive at a steady speed between 15-75 mph (24-120 km/h) for 1 minute or more

   Signal	Current conditions
   	Values	Unit
   ECT Sensor 1
   Engine Speed
   Vehicle Speed

   -6. Monitor the OBD STATUS for DTC P2096 and/or P2097 with the HDS.

   DTC Description	OBD STATUS
   P2096 Post Catalyst Fuel Trim System Too Lean
   P2097 Post Catalyst Fuel Trim System Too Rich

   Does the HDS indicate FAILED?

   YES 

   The failure is duplicated. Go to step 2.

   NO 

   If the HDS indicates PASSED, there is an intermittent failure and the system is OK at this time. Check for poor connections or loose terminals at the A/F sensor (Sensor 1), the secondary HO2S (Sensor 2), and the PCM. If the on-board snapshot of this DTC is recorded, try to reproduce the failure under the same conditions with the on-board snapshot . If the HDS indicates EXECUTING, keep the test conditions until a result comes on. If the HDS indicates OUT OF CONDITION, go to step 1-5 and recheck.

2. Exhaust system check

   -1. Turn the vehicle to the OFF (LOCK) mode.

   -2. Check for leakage, clogging, or blockage in the exhaust system.

   Is there leakage in the exhaust system between the A/F sensor (Sensor 1) and the secondary HO2S (Sensor 2), or any clogging or restrictions in the exhaust system?

   YES 

   Repair or replace the exhaust system .

   NO 

   Go to step 3.

3. A/F sensor (Sensor 1) check

   -1. Substitute a known-good A/F sensor (Sensor 1) .

   -2. Reconnect all connectors.

   -3. Turn the vehicle to the ON mode.

   -4. Reset the PCM with the HDS .

   Reset PCM

   -5. Enter the maintenance mode, then start the engine .

   -6. Hold the engine speed at 3, 000 rpm without load (in P or N) until the radiator fan comes on, then let it idle.

   Test-drive the vehicle under these conditions:

   • ECT Sensor 1 above 158 deg.F (70 deg.C)
   • Transmission in D
   • Engine speed below 4, 000 rpm
   • Drive at a steady speed between 15-75 mph (24-120 km/h) for 1 minute or more

   Signal	Current conditions
   	Values	Unit
   ECT Sensor 1
   Engine Speed
   Vehicle Speed

   -8. Monitor the OBD STATUS for DTC P2096 and/or P2097 with the HDS.

   DTC Description	OBD STATUS
   P2096 Post Catalyst Fuel Trim System Too Lean
   P2097 Post Catalyst Fuel Trim System Too Rich

   Does the HDS indicate PASSED?

   YES 

   Replace the original A/F sensor (Sensor 1) .

   NO 

   If the HDS indicates FAILED, replace the secondary HO2S (Sensor 2) . If the HDS indicates EXECUTING, keep the test conditions until a result comes on. If the HDS indicates OUT OF CONDITION, go to step 3-7 and recheck.