Owners of 2016-2018 Mazda CX-9 vehicles produced before Nov. 10, 2017, may experience a lack of power with no warning lights illuminated and no related DTCs stored. This concern most likely occurs when fuel temperature is high and during situations where high power is required.
This concern may be caused when the learning value for the low pressure fuel pump exceeds a certain level and the PCM limits engine power to avoid a lack of fuel injection. Even if the low pressure fuel pump has a problem, no DTCs are stored.
To eliminate the concern, the PCM control logic has been modified not to limit engine power. After this modification, DTCs P0192:00 or P0087:00 are stored when the fuel injection amount is insufficient.
P0192:00......high fuel pressure sensor circuit low input
P0087:00.....high fuel pressure sensor circuit range/performance problem
Inspect the low pressure fuel pump using the Mazda Modular Diagnostic system (M-MDS). If the low pressure fuel pump exhibits normal performance, reprogram the PCM without replacing the fuel pump. If the low pressure fuel pump exhibits poor performance, replace it after reprogramming the PCM.
1. Connect the M-MDS to the DLC-2.
2. Warm up the engine and leave it at idle with the least amount of electrical loads on.
3. After the vehicle is identified, select the following items from the initialization screen of the M-MDS:
- Select Datalogger
- Select Modules
- Select PCM
4. Select the following PID from the PID table:
- FP_DUTY (fuel pump control module control duty value)
- FUEL_LO_T (fuel temperature inside the fuel supply line)
5. Mark a point on the graph for the PID data and verify if the point is located above the line (in the poor performance area) or below the line (in the normal performance area). For example, if FP_DUTY is 55% and FUEL_LO_T is 40 C, the point is located in the poor performance areas.
6. Reboot the IDS to clear memory before reprogramming.
7. Using IDS 108.03 or later software, reprogram the PCM to the latest calibration.
8. After performing the PCM reprogramming procedure, clear all DTCs.
9. After clearing DTCs, start the engine and confirm that no warning lights are on.
If the PID data is in the poor performance area, replace the low pressure fuel pump.