LEMON Manuals: Even more car manuals for everyone
Home >> Mazda >> 2006 >> 6 s, 4D Wagon, Automatic >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 10 (Symptom Troubleshooting [Engine Control System L3 With TC)) >> No. 11 Engine Stalls/Quits, Engine Runs Rough, Misses, Buck/Jerk, Hesitation/Stumble, Surges >> Diagnostic procedure

Diagnostic procedure

WARNING: This page is about a different variant/trim than selected.
DIAGNOSTIC PROCEDURE

STEP INSPECTION RESULTS ACTION
1 Inspect for the following:
  • Fuel quality (proper octane, contamination, winter/summer blend)
  • Air leakage from intake-air system
  • Intake-air system restriction
  • Air cleaner element
  • Clutch slippage
  • Fuel leakage from fuel line
  • Vacuum leakage

Are all items normal?
Yes Go to the next step.
No Service if necessary.
Repeat Step 1.
2 Perform the self-test function using the WDS or equivalent.
Turn the ignition switch to the ON position.
Retrieve any DTCs.
Is a DTC displayed?
Yes DTC is displayed: 
Go to the appropriate DTC test.
(See DTC TABLE ).
No No DTC is displayed: 
Go to the next step.
3 Access the ECT PID.
Verify that the ECT PID is less than 116°C {241°F}  during driving.
Is the ECT PID less than specified?
Yes Go to the next step.
No The cause of this concern could be from the cooling system overheating.
Perform the symptom troubleshooting "NO.17 COOLING SYSTEM CONCERNS - OVERHEATING."
(See NO. 17 COOLING SYSTEM CONCERNS-OVERHEATING ).
4 Perform the Main Relay Operation Inspection with wiggle the related harness.
(See MAIN RELAY OPERATION INSPECTION ).
Does the main relay operate properly?
Yes Go to the next step.
No Repair or replace for the intermittent fault.
5 Inspect CMP and CKP sensor for the following;

Is there any malfunction detected?
Yes Repair or replace the malfunctioning part according to the inspection results.
No Go to the next step.
6 Connect the WDS or equivalent to DLC-2.
Access and monitor following PIDs using the data monitor function while wiggle the harness and under trouble condition.
  • APP
  • ECT
  • MAF
  • IAT
  • IAT2
  • MAP
  • FP
  • VSS
  • O2S11
  • O2S12
  • LONGFT1
  • SHTFT1
  • CPP (PCM terminal 1H)
  • PNP (PCM terminal 1W)

Do the PIDs indicate correct values?
(See USING THE WDS OR EQUIVALENT ).
Yes Go to the Step 13.
No Inspect and repair or replace suspected parts and related harnesses.
If the malfunction remains, perform the intermittent concern troubleshooting.
(See INTERMITTENT CONCERN TROUBLESHOOTING ).
If the MAP PID remains without specified, go to the next step.
7 Perform the EGR system operation inspection.
(See EGR CONTROL SYSTEM INSPECTION ).
Does EGR system operate properly?
Yes Go to the next step.
No Inspect or replace the malfunctioning parts, according to the inspection results.
8 Perform the A/C Cut-off Operation Inspection.
(See A/C CUT-OFF CONTROL SYSTEM INSPECTION ).
Does the A/C Cut-off Operation work properly?
Yes Go to the next step.
No Repair or replace malfunctioning parts, according to inspection results.
9 Perform the TP sweep inspection.
(See THROTTLE POSITION (TP) SWEEP INSPECTION ).
Does the electronic throttle control system work properly?
Yes Visually inspect the throttle body (damaged/scratching). If normal, go to the next step.
No Inspect or replace the malfunctioning parts, according to the inspection results.
10 Perform the Variable Swirl Control System Operation Inspection.
(See VARIABLE SWIRL SYSTEM OPERATION INSPECTION ).
Does the variable swirl system work properly?
Yes Go to the next step.
No Inspect or replace the malfunctioning parts, according to the inspection results.
11 Perform the Purge Control System Operation Inspection.
(See PURGE CONTROL SYSTEM INSPECTION ).
Does the purge control system work properly?
Yes Go to the next step.
No Inspect or replace the malfunctioning parts, according to the inspection results.
12 Perform the Fuel Pump Speed Control Inspection.
(See FUEL PUMP SPEED CONTROL INSPECTION ).
Does the fuel pump speed control work properly?
Yes Go to the next step.
No Inspect or replace the malfunctioning parts, according to the inspection results.
13 Perform the Wastegate Control System Operation Inspection.
(See WASTEGATE CONTROL SYSTEM OPERATION INSPECTION ).
Does the wastegate control system work properly?
Yes Go to the next step.
No Inspect or replace the malfunctioning parts, according to the inspection results.
14 Remove the parts necessary to inspect turbocharger without remove the turbocharger.
Inspect if turbocharger compressor wheel is bent, damaged, or interfering with housing on vehicle.
(See TURBOCHARGER INSPECTION ).
Is there any problem?
Yes Replace the turbocharger.
No Go to the next step.
15 Inspect the turbocharger compressor wheel locknut is loose or has fallen down inside turbocharger.
Is there any problem?
Yes Replace the turbocharger.
No Go to the next step.
16 Inspect if turbocharger compressor wheel by hand.
Does the wheel turn easily and smoothly?
Yes Go to the next step.
No Replace the turbocharger.
17 Inspect the turbocharger turbine wheel is damaged, cracked or interfering with housing on vehicle.
NOTE:
  • Inspect all fins on each turbine wheel.

Is there any problem?
Yes Replace the turbocharger.
No Go to the next step.
18 Is any engine oil found inside turbocharger turbine housing? Yes Excessive amount of oil is found: 
Replace the turbocharger.
Small amount of oil is found: 
Wipe oil out of vehicle, then go to the next step.
No Go to the next step.
19 Is any engine oil found inside turbocharger compressor housing? Yes Wipe oil out vehicle and install all removed parts in Step 14. Then, go to the next step.
No Turbocharger is normal.
Install all parts removed in Step 14.
Then, go to the next step.
20 Inspect for restriction in the exhaust system and three-way catalytic converter (TWC).
Is there any restriction?
Yes Replace the malfunctioning part.
No Go to the next step.
21 Remove and shake the PCV valve.
Does the PCV valve rattle?
Yes Go to the next step.
No Replace the PCV valve.
22 Perform the spark test.
(See SPARK TEST ).
Is a strong blue spark visible at each cylinder?
Yes Go to the next step.
No Inspect or replace the malfunctioning parts, according to the inspection results.
23 Access and monitor the FUEL_PRES PID.
Is the FUEL_PRES PID value within the specification?
(See USING THE WDS OR EQUIVALENT ).
Yes Go to Step 27.
No Go to the next step.
24 Is the vehicle accelerate performance normally? Yes Go to the next step.
No Go to Step 26.
25 Inspect the fuel pressure sensor.
(See FUEL PRESSURE SENSOR INSPECTION ).
Is the fuel pressure sensor normal?
Yes Go to the Step 27.
No Replace the delivery pipe.
26 Replace the high pressure fuel pump.
Monitor FUEL_PRES PID.
Is the FUEL_PRES PID value within the specified?
(See USING THE WDS OR EQUIVALENT ).
Yes Troubleshooting is completed.
Go to Step 30.
No Go to the next step.
27 Connect the fuel pressure gauge between the fuel pump and the high pressure fuel pump.
Measure the fuel pressure line of the low pressure side.
(See FUEL LINE PRESSURE INSPECTION ).
Is the fuel pressure with in the specification?
Yes Go to the next step.
No Inspect for the following:
  • Fuel line restriction
  • Fuel filter clogging

If normal replace the fuel pump.
28 Inspect the fuel injector for each cylinder.
(See FUEL INJECTOR INSPECTION ).
Are fuel injectors normal?
Yes Go to the next step.
No Replace the suspected fuel injector.
(See FUEL INJECTOR REMOVAL/INSTALLATION ).
29 Measure the compression pressure for each cylinder.
(See COMPRESSION INSPECTION ).
Are compression pressures within the specification?
Yes Replace the injector driver module.
If the problem remains, overhaul the engine.
No Inspect for the following:
  • Damaged valve seat
  • Worn valve stem and valve guide
  • Worn or stuck piston ring
  • Worn piston, piston ring or cylinder
  • Improper valve timing

Service if necessary.
30 Verify test results.
  • If normal, return to the diagnostic index to service any additional symptoms.
  • If a malfunction remains, inspect the related Service Bulletins and/or On-line Repair Information and perform the repair or diagnosis.
    • If the vehicle is repaired, troubleshooting is completed.
    • If the vehicle is not repaired or additional diagnostic information is not available, reprogram the PCM if a later calibration is available. Retest.