NO.10 LOW IDLE/STALLS DURING DECELERATION [L8, LF]

id0103a0801600

10

LOW IDLE/STALLS DURING DECELERATION

DESCRIPTION

•  Engine stops unexpectedly at the beginning of deceleration or recovery from deceleration.

POSSIBLE CAUSE

•  Improper operation of A/C magnetic clutch

•  Air leakage from intake-air system

•  Vacuum leakage

•  Improper operation of electronic throttle control system

•  Improper air/fuel mixture ratio control

•  EVAP control system malfunction

•  Improper load signal input

―  APP sensor

―  TP sensor

―  MAF sensor

―  VSS

―  Brake switch

―  CPP switch (MT)

―  Neutral switch (MT)

―  TR switch (AT)

•  PCM malfunction

10	LOW IDLE/STALLS DURING DECELERATION
DESCRIPTION	• Engine stops unexpectedly at the beginning of deceleration or recovery from deceleration.
POSSIBLE CAUSE	• Improper operation of A/C magnetic clutch • Air leakage from intake-air system • Vacuum leakage • Improper operation of electronic throttle control system • Improper air/fuel mixture ratio control • EVAP control system malfunction • Improper load signal input ― APP sensor ― TP sensor ― MAF sensor ― VSS ― Brake switch ― CPP switch (MT) ― Neutral switch (MT) ― TR switch (AT) • PCM malfunction

Diagnostic procedure

STEP	INSPECTION	RESULTS	ACTION
1	Does the engine idle rough?	Yes	Go to the symptom troubleshooting “NO.8 ENGINE RUNS ROUGH/ROLLING IDLE”. (See NO.8 ENGINE RUNS ROUGH/ROLLING IDLE [L8, LF].)
1	Does the engine idle rough?	No	Go to the next step.
2	Note • Following test is for low idle/stalls during deceleration with A/C on concerns. If other symptoms exist, go to the next step. Turn off the A/C switch and fan switch. Does the A/C magnetic clutch engage?	Yes	Go to the 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 [L8, LF].)
2		No	Go to the next step.
3	Verify the following: • No air leakage from intake-air system • Proper routing and no damage of vacuum lines Is there any malfunction?	Yes	Repair or replace the malfunctioning part according to the inspection results. Repeat Step 3.
3		No	Go to the next step.
4	Connect the M-MDS to the DLC-2. Perform the KOEO/KOER self test and the DTC Reading Procedure. (See KOEO/KOER SELF TEST [L8, LF].) (See ON-BOARD DIAGNOSTIC TEST [L8, LF].) Are any DTCs present?	Yes	Go to the appropriate DTC inspection. (See DTC TABLE [L8, LF].)
4		No	Go to the next step.
5	Perform the Electronic Throttle Control System Inspection. (See ENGINE CONTROL SYSTEM OPERATION INSPECTION [L8, LF].) Does the electronic throttle control system operate properly?	Yes	Go to the next step.
5		No	Repair or replace the malfunctioning part according to the inspection results.
6	Disconnect the vacuum hose between the purge solenoid valve and the intake manifold from the purge solenoid valve side. Plug opening end of vacuum hose. Drive the vehicle. Does the engine condition improve?	Yes	Inspect the EVAP control system. Repair or replace the malfunctioning part according to the inspection results.
6		No	Go to the next step.
7	Connect the M-MDS to the DLC-2. Perform the PID/DATA Monitor and Record Procedure and access the following PIDs: (See ON-BOARD DIAGNOSTIC TEST [L8, LF].) (See PID/DATA MONITOR INSPECTION [SJ6A-EL].) PCM PID: • APP1 • APP2 • TP • MAF • VSS • BOO • CPP (MT) • CPP/PNP (MT) TCM PID: • TR (AT) Are the PIDs normal? (See PCM INSPECTION [L8, LF].) (See PID/DATA MONITOR INSPECTION [SJ6A-EL].)	Yes	Intermittent concern exists. • Perform the “INTERMITTENT CONCERN TROUBLESHOOTING”. (See INTERMITTENT CONCERN TROUBLESHOOTING [L8, LF].)
7		No	APP1, APP2: • Inspect the APP sensor. (See ACCELERATOR PEDAL POSITION (APP) SENSOR INSPECTION [L8, LF].) TP: • Inspect the TP sensor. (See THROTTLE POSITION (TP) SENSOR INSPECTION [L8, LF].) MAF: • Inspect the MAF sensor. (See MASS AIR FLOW (MAF) SENSOR INSPECTION [L8, LF].) VSS: • Inspect the VSS. (See VEHICLE SPEED SENSOR (VSS) INSPECTION [SJ6A-EL].) BOO: • Inspect the brake switch. (See BRAKE SWITCH INSPECTION.) CPP (MT): • Inspect the CPP switch. (See CLUTCH PEDAL POSITION (CPP) SWITCH INSPECTION [L8, LF].) CPP/PNP (MT): • Inspect neutral switch. (See NEUTRAL SWITCH INSPECTION [L8, LF].) TR (AT): • Inspect the TR switch. (See TRANSMISSION RANGE (TR) SWITCH INSPECTION [SJ6A-EL].) Repair or replace the malfunctioning part according to the inspection results.
8	Verify test results. • If normal, return to diagnostic index to service any additional symptoms. (See ENGINE SYMPTOM TROUBLESHOOTING [L8, LF].) • If malfunction remains, inspect related Service information perform repair or diagnosis. ― If vehicle repaired, troubleshooting completed. ― If vehicle not repaired or additional diagnostic information not available, replace the PCM. (See PCM REMOVAL/INSTALLATION [L8, LF].)