NO.11 ENGINE STALLS/QUITS, ENGINE RUNS ROUGH, MISSES, BUCK/JERK, HESITATION/STUMBLE, SURGES [MZI-3.7]


id0103d2801700

11

ENGINE STALLS/QUITS—ACCELERATION/CRUISE

ENGINE RUNS ROUGH—ACCELERATION/CRUISE

MISSES—ACCELERATION/CRUISE

BUCK/JERK—ACCELERATION/CRUISE/DECELERATION

HESITATION/STUMBLE—ACCELERATION

SURGES—ACCELERATION/CRUISE

DESCRIPTION
•  Engine stops unexpectedly at beginning of acceleration or during acceleration.
•  Engine stops unexpectedly while cruising.
•  Engine speed fluctuates during acceleration or cruising.
•  Engine misses during acceleration or cruising.
•  Vehicle bucks/jerks during acceleration, cruising, or deceleration.
•  Momentary pause at beginning of acceleration or during acceleration.
•  Momentary minor irregularity in engine output.
POSSIBLE CAUSE
•  Drive-by-wire control system operates with brake override system.
•  Vacuum leakage
•  Air cleaner restriction
•  Air leakage from intake-air system parts
•  Intake air system restriction
•  Poor fuel quality
•  Disconnected electrical system connector
•  Loose attaching bolts or worn engine mounts
•  PCM DTC is stored.
•  Engine overheating
•  Throttle body restriction or clogged
•  Erratic signal to PCM
―  APP sensor or related circuit malfunction
―  TP sensor or related circuit malfunction
―  CKP sensor or related circuit malfunction
―  MAF sensor or related circuit malfunction
―  TP sensor or related circuit malfunction
―  Battery or related circuit malfunction
―  VSS or related circuit malfunction
•  Erratic signal from CKP sensor
•  Fuel leakage from fuel injector
•  Fuel injector clogging
•  Improper operation of drive-by-wire control system
•  Restriction in exhaust system
•  Inadequate fuel pressure
―  Intermittent open or short circuit in fuel pump circuit
―  Fuel pump mechanical malfunction
―  Fuel line restriction or clogging
―  Pressure regulator malfunction (built-in fuel pump unit)
•  Fuel leakage from fuel system
•  Improper A/C system operation
•  Improper operation of cruise control system
•  Improper air/fuel mixture ratio control operation
•  Front HO2S or related circuit malfunction (PCM connector (2 types))
•  A/F sensor or related circuit malfunction (PCM connector (3 types))
•  PCV valve malfunction
•  Check valve (two-way) malfunction integrated with fuel tank
•  Purge solenoid valve malfunction
•  Fuel flow into evaporative purge hose
•  Erratic signal or no signal from CMP sensor
•  Low engine compression
•  Improper valve timing due to jumping out timing chain
•  ATX malfunction
Warning
•  The following troubleshooting flow chart contains the fuel system diagnosis and repair procedures. Read the following warnings before servicing the fuel system:
―  Fuel vapor is hazardous. It can easily ignite, causing serious injury and damage. Always keep sparks and flames away from fuel.
―  Fuel line spills and leakage are dangerous. Fuel can ignite and cause serious injuries or death and damage. Fuel can also irritate skin and eyes. To prevent this, always complete “BEFORE SERVICE PRECAUTION” and “AFTER SERVICE PRECAUTION” described in this manual. (See BEFORE SERVICE PRECAUTION [MZI-3.7].)(See AFTER SERVICE PRECAUTION [MZI-3.7].)
Caution
•  Disconnecting/connecting quick release connector without cleaning it may cause damage to fuel pipe and quick release connector. Always clean quick release connector joint area before disconnecting/connecting, and make sure that it is free of foreign material.

Diagnostic procedure

STEP

INSPECTION

RESULTS

ACTION

1
Retrieve any PCM DTCs using the M-MDS.
Is the DTC P2299:00 displayed?
Yes
Go to the appropriate DTC inspection. (Drive-by-wire control system operates with brake override system.)
No
Go to the next step.
2
Verify the following:
•  Vacuum connection
•  Air cleaner element
•  No air leakage from intake-air system
•  No restriction of intake-air system
•  Proper sealing of intake manifold and components attached to intake manifold
•  Ignition wiring
•  Fuel quality (such as proper octane, contamination, winter/summer blend)
•  Electrical connections
•  Smooth operation of throttle valve
•  Engine mount installation
Are all items normal?
Yes
Go to the next step.
No
Repair or replace the malfunctioning part according to the inspection results.
Repeat Step 2.
3
Turn the ignition switch to the ON position (Engine off).
Retrieve any PCM DTCs using the M-MDS.
Are there any DTCs displayed?
Yes
DTC is displayed:
•  Go to the appropriate DTC inspection.
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”.
No
Go to the next step.
5
Visually inspect the throttle valve.
Are any foreign materials adhere to around throttle valve?
Yes
Clean the throttle valve.
No
Go to the next step.
6
Caution
•  While performing this step, always operate the vehicle in a safe and lawful manner.
•  When the M-MDS is used to observe monitor system status while driving, be sure to have another technician with you, or record the data in the M-MDS using the PID/DATA MONITOR AND RECORD capturing function and inspect later.
Access the following PCM PIDs and VSS using the M-MDS:
•  APP1
•  APP2
•  APP3 (PCM connector (2 types))
•  RPM
•  VPWR
•  TP1
•  TP2
•  MAF
•  VSS
Monitor each PID while driving the vehicle.
Do the PIDs indicate the correct values under trouble condition?
Yes
Go to the next step.
No
APP1, APP2 or APP3 PID is not normal:
•  Inspect if output signal from APP sensor changes smoothly.
RPM PID is not normal:
•  Inspect the CKP sensor and related wiring harness for vibration or intermittent open/short circuit.
VPWR PID is not normal:
•  Inspect for open circuit intermittently.
TP1 or TP2 PID is not normal:
•  Inspect if output signal from TP sensor changes smoothly.
MAF PID is not normal:
•  Inspect for open circuit of the MAF sensor and related wiring harness intermittently.
VSS PID is not normal:
•  Inspect for open circuit of VSS and related wiring harness intermittently.
Repair or replace the malfunctioning part according to the inspection results.
7
Inspect the CKP sensor.
Is the CKP sensor normal?
Yes
Go to the next step.
No
Repair or replace the malfunctioning part according to the inspection results.
8
Verify the spark plug conditions.
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 fuel injector.
Spark plug is grayish white:
•  Inspect the fuel injector for clogging.
Repair or replace the malfunctioning part according to the inspection results.
No
Install the spark plugs on original cylinders.
Go to the next step.
9
Perform the drive-by-wire control system operation inspection.
Does the drive-by-wire control system function properly?
Yes
Go to the next step.
No
Repair or replace the malfunctioning part according to the inspection results.
10
Visually inspect the exhaust system part.
Is there any deformed exhaust system part?
Yes
Repair or replace the malfunctioning part according to the inspection results.
No
Go to the next step.
11
Inspect the fuel line pressure.
Is the fuel line pressure correct?
Yes
Go to the next step.
No
Zero or low:
•  Inspect the following:
―  Fuel pump relay
―  Fuel pump circuit
―  Fuel line for clogging
•  If there is no malfunction, replace the fuel pump unit. (Fuel pump or pressure regulator malfunction)
High:
•  Replace the fuel pump unit. (Pressure regulator malfunction)
12
Visually inspect for fuel leakage at fuel injector, O-ring, and fuel line.
Is there any fuel leakage?
Yes
Repair or replace the malfunctioning part according to the inspection results.
No
Go to the next step.
13
Note
•  The following test is for stall concerns with the A/C on. If other symptoms exist, go to the next step.
Connect the pressure gauges to A/C low and high pressure side lines.
Turn the A/C on and measure low side and high side pressures.
Are pressures within specifications?
Yes
Go to the next step.
No
If the A/C is always on:
•  Go to the symptom troubleshooting “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
•  Repair or replace the malfunctioning part according to the inspection results.
14
Note
•  The following test should be performed for symptom with cruise control ON. If other symptoms exist, go to the next step.
Inspect the cruise control system operation.
Is the cruise control system normal?
Yes
Go to the next step.
No
Repair or replace the malfunctioning part according to the inspection results.
15
Inspect the following:
•  PCM connector (2 types):
•  PCM connector (3 types):
Is there any malfunction?
Yes
PCM connector (2 types):
PCM connector (3 types):
No
Go to the next step.
16
Note
•  The PCV valve cannot be reassembled once it is removed because the tabs will have bee n broken. Inspect the PCV valve without removing it from the vehicle.
Inspect the PCV valve with it installed.
Is the PCV valve normal?
Yes
Go to the next step.
No
Replace the PCV valve.
17
Inspect the evaporative purge hose between fuel tank and purge solenoid valve.
Does the fuel flow into evaporative purge hose?
Yes
Inspect the check valve (two-way).
Repair or replace the malfunctioning part according to the inspection results.
No
Go to the next step.
18
Disconnect the vacuum hose between purge solenoid valve and intake manifold from purge solenoid side.
Plug opening end of vacuum hose.
Drive the vehicle.
Does the engine condition improve?
Yes
Inspect the following:
•  If purge solenoid valve is stuck open.
•  EVAP control system
Repair or replace the malfunctioning part according to the inspection results.
No
Go to the next step.
19
Inspect the CMP sensor.
Is the CMP sensor normal?
Yes
Go to the next step.
No
Repair or replace the malfunctioning part according to the inspection results.
20
Is the engine compression correct?
Yes
Inspect the following:
•  Valve timing
•  Internal transaxle part
•  Engine mounts
•  Check valve (two-way)
Repair or replace the malfunctioning part according to the inspection results.
No
Inspect for cause.
Repair or replace the malfunctioning part according to the inspection results.
21
•  Verify test results.
―  If normal, return to diagnostic index to service any additional symptoms.
―  If malfunction remains, inspect related Service Information and perform repair or diagnosis.
•  If vehicle is repaired, troubleshooting completed.
•  If vehicle is not repaired or additional diagnostic information is not available, replace the PCM.