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Home >> Mazda >> 2002 >> Tribute LX, 4WD >> Repair and Diagnosis >> External Pages >> Different car >> Section 434 (Symptom Troubleshooting [Engine]) >> No.12 Lack/Loss Of Power-Acceleration/Cruise >> Diagnostic procedure

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.
NO.12 LACK/LOSS OF POWER-ACCELERATION/CRUISE DIAGNOSTIC PROCEDURE

STEP INSPECTION RESULTS ACTION
1 Does the engine knock/ping/detonate? Yes Go to the symptom troubleshooting "No. 13 Knocking/pinging/detonation-Acceleration/cruise".
(See NO.13 KNOCKING/PINGING/DETONATION-ACCELERATION/CRUISE .)
No Go to the next step.
2 Verify the following:
  • Vacuum connection
  • Air cleaner element
  • Fresh air duct
  • Air cleaner
  • No air leakage from intake-air system
  • No restriction of intake-air system
  • Blockage of intake-air system (between MAF sensor and intake ports)
  • MAF sensor installation
  • Exhaust manifold (leakage, damaged)
  • Fuel quality (e.g. proper octane, contamination, winter/summer blend)
  • Tire pressure

Are all the items normal?
Yes Go to the next step.
No Service if necessary.
Repeat Step 2.
3 Connect the WDS or equivalent to the DLC-2.
Turn the ignition switch to the ON position (Engine off).
Retrieve any DTCs.
Are there any DTCs displayed?
Yes DTC is displayed: 
Go to the applicable DTC inspection.
(See DTC TABLE .)
No No DTC is displayed: 
Go to the next step.
4 Is the engine overheating? Yes Go to the symptom troubleshooting "No.17 Cooling system concerns - Overheating".
(See NO.17 COOLING SYSTEM CONCERNS-OVERHEATING .)
No Go to the next step.
5 Connect the WDS or equivalent to the DLC-2.
Access the APP1, APP2, RPM, MAF, O2S11, O2S12, TP_REL and VSS PIDs.
Drive vehicle while monitoring the PIDs.
Are the PIDs within the specifications?
(See PCM INSPECTION .)
Yes Go to the next step.
No APP1, APP2 PIDs: 
Inspect if the output signal APP sensor changes smoothly.
RPM PID: 
Inspect the eccentric shaft position sensor and the related wiring harness for vibration or an intermittent open/short circuit or both. If normal, go to Step 7.
MAF PID: 
Inspect for an intermittent open circuit of the MAF sensor and the related wiring harness.
O2S11 PID: 
Inspect the front HO2S and the related wiring harness for vibration or an intermittent open or short circuit or both. If normal, go to Step 8.
O2S12 PID: 
Inspect the rear HO2S and the related wiring harness for vibration or an intermittent open or short circuit or both. If normal, go to Step 8.
TP_REL PID: 
Inspect if the output signal TP sensor changes smooth.
VSS PID: 
Inspect ABS or DCS.
(See DTC TABLE .)
(See DTC TABLE .)
6 Inspect the knock sensor.
(See KNOCK SENSOR (KS) INSPECTION .)
Is the knock sensor normal?
Yes Go to the next step.
No Replace the knock sensor.
(See KNOCK SENSOR (KS) REMOVAL/INSTALLATION .)
7 Visually inspect the eccentric shaft position sensor and the teeth of the pulse wheel.
Are the eccentric shaft position sensor and the teeth of the pulse wheel normal?
Yes Go to the next step.
No Replace the malfunctioning parts.
8 Is a strong blue spark visible at each disconnected high-tension lead while cranking the engine? Yes Inspect for the following:
  • Spark plugs malfunction
  • Spark plugs heat range
  • Pulse wheel damaged on eccentric shaft
  • Open or short circuit on eccentric shaft position sensor
  • Open or short between eccentric shaft position sensor and PCM terminal 2U or 2X

If they are normal, go to the next step.
No Inspect for the following:
  • High-tension leads
  • Ignition coils or connectors
9 Inspect the spark plug condition.
Is the spark plug wet, covered with carbon or grayish white?
Yes Spark plug is wet or covered with carbon: 
Inspect for fuel leakage from the fuel injector.
Inspect the spark plug and the high-tension lead.
Spark plug is grayish white: 
Inspect for clogged fuel injector.
No Install the spark plugs on original rotors.
Go to the next step.
10 Perform the drive-by-wire control system operation inspection.
(See DRIVE-BY-WIRE CONTROL SYSTEM INSPECTION .)
Does the drive-by-wire control system work properly?
Yes Go to the next step.
No Repair or replace the malfunctioning part according to the drive-by-wire control system operation inspection results.
11 Visually inspect the exhaust system part.
Is there any deformed exhaust system part?
Yes Replace the suspected part.
No Go to the next step.
12 Perform the fuel pump speed control operation inspection.
(See FUEL PUMP SPEED CONTROL OPERATION INSPECTION .)
Does the fuel pump speed control operate properly?
Yes Go to the next step.
No Repair or replace the malfunctioning parts, according to the fuel pump speed control operation inspection results.
13 Disconnect the fuel line quick release connector and install the fuel gauge to the fuel line.
Short the check connector terminal F/P to the body GND using a jumper wire.
Turn the ignition switch to the ON position.
Is the fuel line pressure correct with the ignition switch at the ON position?
(See FUEL LINE PRESSURE INSPECTION .)
Yes Go to the next step.
No Zero or low: 
Inspect the fuel pump relay and the fuel pump circuit.
Inspect for clogged fuel line.
If normal, replace the fuel pump unit.
(See FUEL PUMP UNIT REMOVAL/INSTALLATION .)
High: 
Replace the fuel pump unit.
(See FUEL PUMP UNIT REMOVAL/INSTALLATION .)
14 Perform the fuel injector operation inspection.
(See FUEL INJECTOR OPERATION INSPECTION .)
Are the fuel injectors operating properly?
Yes Go to the next step.
No Repair or replace the malfunctioning parts, according to the fuel injector operation inspection results.
15 Inspect the fuel injectors for the following:
(See FUEL INJECTOR INSPECTION .)
  • Leakage
  • Clogging
  • Injection amount

Are the injectors normal?
Yes Go to the next step.
No Replace the fuel injector.
(See FUEL INJECTOR REMOVAL/INSTALLATION .)
16 Perform the SSV operation inspection.
(See SECONDARY SHUTTER VALVE (SSV) OPERATION INSPECTION .)
Does the SSV operate properly?
Yes Go to the next step.
No Repair or replace the malfunctioning parts, according to the SSV operation inspection results.
17 Perform the VDI operation inspection.
(See VARIABLE DYNAMIC EFFECT INTAKE-AIR (VDI) OPERATION INSPECTION .)
Does the VDI operate properly?
Yes Go to the next step.
No Repair or replace the malfunctioning parts, according to the VDI operation inspection results.
18
NOTE:
  • The following test is for 13B-MSP (High Power). Go to the next step for 13B-MSP (Standard Power).
Perform the APV control inspection.(See AUXILIARY PORT VALVE (APV) CONTROL INSPECTION .)Does the APV control operate properly?
Yes Go to the next step.
No Repair or replace the malfunctioning parts, according to the APV control inspection results.
19
NOTE:
  • The following test is for engine stalling with A/C on concern. If other symptoms exist, go to the next step.
Connect the pressure gauge to the A/C low and high side pressure lines.Turn the A/C on and measure the low side and high side pressures.Are pressures within the specifications?(See REFRIGERANT PRESSURE CHECK .)
Yes Go to the next step.
No If the A/C is always on, go to symptom troubleshooting "No.24 A/C is always on or A/C compressor runs continuously".
(See NO.24 A/C IS ALWAYS ON OR A/C COMPRESSOR RUNS CONTINUOUSLY .)
For other symptoms, inspect the following:
  • Refrigerant charging amount
  • Condenser fan operation
20 Inspect for A/C cut-off operation.
(See A/C CUT-OFF CONTROL SYSTEM INSPECTION .)
Does the A/C cut-off work properly?
Yes Go to the next step.
No Inspect A/C cut-off system components, the
21 Disconnect the vacuum hose between the purge solenoid valve and the intake manifold at the quick release connector.
Plug the opening end of the vacuum hose.
Drive the vehicle.
Does the engine condition improve?
Yes Inspect if the purge solenoid valve is stuck open mechanically.
Inspect the evaporative emission control system.
No Go to the next step.
22 Perform the metering oil pump control inspection.
(See METERING OIL PUMP CONTROL INSPECTION .)
Does the metering oil pump control properly?
Yes Go to the next step.
No Repair or replace the malfunctioning parts, according to the metering oil pump inspection results.
23 Inspect the engine compression.
(See COMPRESSION INSPECTION .)
Is it normal?
Yes Inspect the following:
  • Ignition timing
  • Internal transmission components (AT)
  • Torque converter clutch control (AT)
  • Clutch (MT)
  • Brake system for dragging
  • Knock sensor
No Go to the next step.
24 Perform the metering oil pump control inspection.
(See METERING OIL PUMP CONTROL INSPECTION .)
Does the metering oil pump control operate properly?
Yes Go to the next step.
No Repair or replace the malfunctioning part according to the inspection results.
After that overhaul or replace the engine.
(See ENGINE REMOVAL/INSTALLATION or OVERHAUL - 1.3L (13B-MSB) .)
25 Check the engine oil condition.
Is the engine oil low viscosity and/or is there a gasoline odor?
Yes Replace the engine oil.
Inspect the ECT sensor and the related wiring harnesses.
(See ENGINE COOLANT TEMPERATURE (ECT) SENSOR INSPECTION .)
After that overhaul or replace the engine.
(See ENGINE REMOVAL/INSTALLATION or OVERHAUL - 1.3L (13B-MSB) .)
No Go to the next step.
26 Inspect the oil pressure.
(See OIL PRESSURE INSPECTION .)
Is the oil pressure within the specification?
Yes Go to the next step.
No Repair or replace the malfunctioning part according to the inspection results.
After that overhaul or replace the engine.
(See ENGINE REMOVAL/INSTALLATION or OVERHAUL - 1.3L (13B-MSB) .)
27 Turn the ignition switch off.
Disconnect the fuel line quick release connector and install the fuel gauge to the fuel line.
Start the engine and run it at idle.
Measure the fuel line pressure at idle.
Is the fuel line pressure correct at idle?
(See FUEL LINE PRESSURE INSPECTION .)
Yes Go to the next step.
No Replace the fuel pump unit.
(See FUEL PUMP UNIT REMOVAL/INSTALLATION .)
After that overhaul or replace the engine.
(See ENGINE REMOVAL/INSTALLATION or OVERHAUL - 1.3L (13B-MSB) .)
28 Check the oil pipe between the metering oil pump and the metering oil nozzle.
Is there any air and/or clogging in the oil pipe?
Yes Inspect and repair for leakage and/or clogging in the oil passage at engine.
After that overhaul or replace the engine.
(See ENGINE REMOVAL/INSTALLATION or OVERHAUL - 1.3L (13B-MSB) .)
No Overhaul or replace the engine.
(See ENGINE REMOVAL/INSTALLATION or OVERHAUL - 1.3L (13B-MSB) .)
29
  • Verify test results.
    • If normal, return to the diagnostic index to service any additional symptoms.
    • If the malfunction remains, inspect the related Service Bulletins and/or the On-line Repair Information and perform the repair or diagnosis.
*: 13B-MSP (High Power)