Diagnostic procedure

1999 Mazda 626 ES, 2.5 D, StandardSECTION Diagnostic procedure
WARNING: This page is about a different car, the 2005 Mazda RX-8. However, it is still accessible from the selected car via links, so may be relevant.
DTC P2097 DIAGNOSTIC PROCEDURE

STEP INSPECTION ACTION
1 VERIFY FREEZE FRAME DATA AND DIAGNOSTIC MONITORING TEST RESULTS HAVE BEEN RECORDED 
  • Have FREEZE FRAME DATA and DIAGNOSTIC MONITORING TEST RESULTS (Fuel system related) been recorded?
Yes Go to the next step.
No Record the FREEZE FRAME DATA and DIAGNOSTIC MONITORING TEST RESULTS on the repair order, then go to the next step.
2 VERIFY RELATED REPAIR INFORMATION AVAILABILITY 
  • Verify related Service Bulletins and/or on-line repair information availability.
  • Is any related repair information available?
Yes Perform repair or diagnosis according to the available repair information.
  • If the vehicle is not repaired, go to the next step.
No Go to the next step.
3 VERIFY RELATED PENDING CODE OR STORED DTC 
  • Turn the ignition switch off, then to the ON position (Engine off).
  • Verify the related PENDING CODE or stored DTCs.
  • Is the DTC P0172 also present?
Yes Go to the DTC P0172 inspection.
(See DTC P0172 .)
No If misfire DTC is present or driveability concern exists, go to step 11.
If misfire DTC is not present and driveability concern does not exist, go to the next step.
4 IDENTIFY TRIGGER DTC FOR FREEZE FRAME DATA 
  • Is DTC P2097 on FREEZE FRAME DATA?
Yes Go to the next step.
No Go to the FREEZE FRAME DATA DTC inspection. (See DTC TABLE .)
5 VERIFY CURRENT INPUT SIGNAL STATUS OF REAR HO2S 
  • Connect the WDS or equivalent to the DLC-2.
  • Start the engine and warm it up completely.
  • Access the O2S12 PID.
  • Read the O2S12 PID under following accelerator pedal condition (in PARK or NEUTRAL).
    • More than 0.55 V  when accelerator pedal is suddenly depressed (rich condition).
    • Less than 0.55 V  just after release of accelerator pedal (lean condition)
  • Is the PID normal?
Yes Go to the next step.
No Visually inspect for the gas leakage between TWC and rear HO2S.

Then go to Step 17.
6 VERIFY CURRENT INPUT SIGNAL STATUS 
  • Connect the WDS or equivalent to the DLC-2.
  • Verify the following PIDs.

    (See PCM INSPECTION .)

    • APP
    • ECT
    • MAF
    • TP
    • VSS
  • Are the PIDs normal?
Yes Go to the next step.
No Inspect the malfunctioning part according to the inspection results.
Then go to Step 17.
7 VERIFY CURRENT INPUT SIGNAL STATUS UNDER FREEZE FRAME DATA CONDITION 
  • Connect the WDS or equivalent to the DLC-2.
  • Verify the following PIDs under the FREEZE FRAME DATA condition.

    (See PCM INSPECTION .)

    • APP
    • ECT
    • MAF
    • TP
    • VSS
  • Are the PIDs normal?
Yes Go to the next step.
No Inspect the malfunctioning part according to the inspection results.
Then go to Step 17.
8 VERIFY CURRENT INPUT SIGNAL STATUS OF FRONT HO2S 
  • Connect the WDS or equivalent to the DLC-2.
  • Start the engine and warm it up completely.
  • Access the O2S11 PID.
  • Read the O2S11 PID under following accelerator pedal condition (in PARK or NEUTRAL).
    • Less than 1 mA  when accelerator pedal is suddenly depressed (rich condition).
    • More than 1 mA  just after release of accelerator pedal (lean condition)
  • Is the PID normal?
Yes Go to the next step.
No Replace the front HO2S.
(See FRONT HEATED OXYGEN SENSOR (HO2S) REMOVAL/INSTALLATION .)
Then go to Step 17.
9 INSPECT FUEL PUMP SPEED CONTROL OPERATION 
Yes Repair or replace the malfunctioning part according to the inspection results.
Then go to Step 17.
No Go to the next step.
10 INSPECT FUEL LINE PRESSURE 
Yes
  • If the fuel line pressure is too low, go to the next step.
  • If the fuel line pressure is too high, replace the fuel pump unit, then go to Step 17.

    (See FUEL PUMP UNIT REMOVAL/INSTALLATION .)

No Go to Step 13.
11 INSPECT LONG TERM FUEL TRIM 
  • Connect the WDS or equivalent to the DLC-2.
  • Access the LONGFT1 PID.
  • Compare the LONGFT1 PID with recorded FREEZE FRAME DATA at Step 1.
  • Is the LONGFT1 PID above FREEZE FRAME DATA?
Yes Inspect the purge solenoid valve.
(See PURGE SOLENOID VALVE INSPECTION .)

Then go to Step 17.
No Go to the next step.
12 INSPECT ENGINE COMPRESSION 
Yes Go to the next step.
No Go to Step 17.
13 INSPECT METERING OIL PUMP 
Yes Repair or replace the malfunctioning part according to the inspection results.
Overhaul or replace the engine.
Then go to Step 17.
No Go to the next step.
14 INSPECT ENGINE OIL CONDITION 
  • Inspect the engine oil condition.
  • Is the engine oil condition normal?
Yes Go to the next step.
No Replace the engine oil.
Inspect the ECT sensor and related harnesses.
(See ENGINE COOLANT TEMPERATURE (ECT) SENSOR INSPECTION .)
Overhaul or replace the engine.
Then go to Step 17.
15 INSPECT OIL PRESSURE 
Yes Repair or replace the malfunctioning part according to the inspection results.
Overhaul or replace the engine.
Then go to Step 17.
No Go to the next step.
16 INSPECT OIL PASSAGE 
  • Inspect the oil pipe between metering oil pump and metering oil nozzle.
  • Is there any malfunction?
Yes Inspect and repair for leakage or clogging in the engine oil passage.
Overhaul or replace the engine.
Then go to the next step.
No Overhaul or replace the engine.
Then go to the next step.
17 VERIFY TROUBLESHOOTING OF DTC P2097 COMPLETED 
  • Make sure to reconnect all disconnected connectors.
  • Clear the DTC from the PCM memory using the WDS or equivalent.
  • Perform the "DRIVE MODE 1".

    (See OBD-II DRIVE MODE .)

  • Is the PENDING CODE same as DTC present?
Yes Replace the PCM, then go to the next step.
(See PCM REMOVAL/INSTALLATION .)
No Go to the next step.
18 VERIFY AFTER REPAIR PROCEDURE 
Yes Go to the applicable DTC inspection.
(See DTC TABLE .)
No DTC troubleshooting completed.
RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • You smell fuel, burning insulation, or see smoke.
  • Brakes feel soft, pull hard to one side, or make grinding noises.
  • The engine overheats, stalls repeatedly, or misfires under load.
  • You are missing required tools, torque specs, or safe lifting equipment.
  • You are not confident in the next step or safety outcome.