Ram B1500, B2500, B3500, 1999-2003

What To Do When There Are No DTCs 2

Print

Other Diagnosis & Testing



2001-03 RAM Pickup & Van 3.7L VIN K 'C1' Black Connector
PCM Pin #Wire ColorCircuit Description (32-Pin)Value at Hot Idle
1TN/ORCoil 3 Driver Control5°, 55 mph: 8° dwell
2LG/BKIgnition Switch Power (Start-Run)12-14v
3TN/LGCoil 4 Driver Control5°, 55 mph: 8° dwell
4BK/LBSensor Ground  
5TN/LBCoil 6 Driver Control5°, 55 mph: 8° dwell
6BR/YLPNP Switch Sense SignalIn P/N: 0v, Others: 5v
7TN/RDCoil 1 Driver Control5°, 55 mph: 8° dwell
8GY/BKCKP Sensor SignalDigital Signals: 0-5-0v
9---Not Used---
10GY/RDIAC 3 Driver ControlPulse Signals
11YL/BKIAC 2 Driver ControlPulse Signals
12YL/BKPower Steering Pressure SwitchStraight: 0v, Turning: 5v
13YLIgnition Switch Power (Start-Run)12-14v
14---Not Used---
15BK/RDIAT Sensor SignalAt 100°F: 1.83v
16TN/BKECT Sensor SignalAt 180°F: 2.80v
17OR5-Volt Supply4.9-5.1v
18TN/YLCMP Sensor SignalDigital Signals: 0-5-0v
19VT/BKIAC 4 Driver ControlPulse Signals
20BR/WTIAC 1 Driver ControlPulse Signals
21TN/DGCoil 3 Driver Control5°, 55 mph: 8° dwell
22RD/WTKeep Alive Power (B+)12-14v
23OR/DBTP Sensor Signal0.6-1.0v
24BK/DGHO2S-11 (B1 S1) Signal0.1-1.1v
25TN/WTHO2S-12 (B1 S2) Signal0.1-1.1v
26---Not Used---
27OR/RDMAP Sensor Signal1.5-1.6v
28-30---Not Used---
31BK/TNPower Ground  
32BK/TNPower Ground  



Click image to see an enlarged view

Fig.

2001-03 RAM Pickup & Van 3.7L VIN K (A/T) 'C3' Gray Connector
PCM Pin #Wire ColorCircuit Description (32-Pin)Value at Hot Idle
1DB/ORA/C Clutch Relay ControlRelay Off: 12v, On: 1v
2, 6, 13, 17---Not Used---
3DB/YLASD Relay ControlRelay Off: 12v, On: 1v
4TN/RDSpeed Control Vacuum SolenoidVacuum Increasing: 1v
5LG/RDSpeed Control Vent SolenoidVacuum Decreasing: 1v
7YL/BKKnock Sensor 1 Signal0.080v AC
8BR/VTHO2S-11 (B1 S1) Heater ControlHeater Off: 12v, On: 1v
9DB/ORHeater Relay Control (Downstream)Relay Off: 12v, On: 1v
10WT/DGLDP Switch SenseLDP Switch Closed: 0v
11YL/RDSpeed Control Power Supply12-14v
12DG/ORASD Relay Power (B+)12-14v
14ORLDP Solenoid ControlPWM Signal: 0-12-0v
15PK/YLBattery Temperature SensorAt 86°F: 1.96v
16BR/WTHO2S-12 (B1 S2) Heater ControlHeater Off: 12v, On: 1v
18BR/VTKnock Sensor 2 Signal0.080v AC
19BRFuel Pump Relay ControlRelay Off: 12v, On: 1v
20PK/BKEVAP Purge Solenoid ControlPWM Signal: 0-12-0v
21-23---Not Used---
24WT/PKBrake Switch SenseBrake Off: 0v, On: 12v
25WT/DBGenerator Field Source12-14v
26LB/BKFuel Level Sensor SignalFull: 0.56v, 1/2 full: 2.5v
27PKSCI Transmit0v
28, 31---Not Used---
29LGSCI Receive5v
30WT/BRPCI Data Bus (J1850)Digital Signals: 0-7-0v
32RD/LGSpeed Control Switch SignalS/C & Set Switch On: 3.8v
2001-03 RAM Pickup & Van 3.7L VIN K (A/T) White 'C2' Connector
PCM Pin #Wire ColorCircuit Description (32-Pin)Value at Hot Idle
1-3---Not Used---
4WT/DBInjector 1 Driver1-4 ms
5YL/WTInjector 3 Driver1-4 ms
6GYInjector 5 Driver1-4 ms
7-8---Not Used---
9TN/PKCoil 1 Driver Control5°, 55 mph: 8° dwell
10DGGenerator Field ControlDigital Signal: 0-12-0v
11-13---Not Used---
15TNInjector 2 Driver1-4 ms
16LB/BRInjector 4 Driver1-4 ms
17DB/YLCondenser Fan Control RelayRelay Off: 12v, On: 1v
18---Not Used---
19DBAC Pressure Sensor Signal0.90v at 79 psi
20-22---Not Used---
23GY/YLEngine Oil Pressure Sensor1.6v at 24 psi
24-26---Not Used---
27WT/ORVehicle Speed SignalDigital Signals
28-30---Not Used---
31VT/WT5-Volt Supply4.9-5.1v
32---Not Used---
2001-03 RAM Van 5.9L VIN Z (A/T) 'C1' Black Connector
PCM Pin #Wire ColorCircuit Description (32-Pin)Value at Hot Idle
1---Not Used---
2LG/BKIgnition Switch Power (B+)12-14v
3---Not Used---
4BK/LBSensor Ground  
5---Not Used---
6BR/YLPNP Switch Sense SignalIn P/N: 0v, Others: 5v
7GYCoil 1 Driver Control5°, 55 mph: 8° dwell
8GY/BKCKP Sensor SignalDigital Signals: 0-5-0v
9---Not Used---
10YL/BKIAC 2 Driver ControlPulse Signals
11BR/WTIAC 1 Driver ControlPulse Signals
12-14---Not Used---
15BK/RDIAT Sensor SignalAt 100°F: 1.83v
16TN/BKECT Sensor SignalAt 180°F: 2.80v
17OR5-Volt Supply4.9-5.1v
18TN/YLCMP Sensor SignalDigital Signals: 0-5-0v
19GY/RDIAC 3 Driver ControlPulse Signals
20VT/BKIAC 4 Driver ControlPulse Signals
21---Not Used---
22DG/BKKeep Alive Power (B+)12-14v
23OR/DBTP Sensor Signal0.6-1.0v
24DB/DGHO2S-11 (B1 S1) Signal0.1-1.1v
25TN/WTHO2S-12 (B1 S2) Signal0.1-1.1v
26---Not Used---
27DG/RDMAP Sensor Signal1.5-1.6v
28-32---Not Used---
2001-03 RAM Van 5.9L VIN Z (A/T) 'C3' Gray Connector
PCM Pin #Wire ColorCircuit Description (32-Pin)Value at Hot Idle
1DB/ORA/C Clutch Relay ControlRelay Off: 12v, On: 1v
2---Not Used---
3DB/YLASD Relay ControlRelay Off: 12v, On: 1v
4TN/RDSpeed Control Vacuum SolenoidVacuum Increasing: 1v
5LG/RDSpeed Control Vent SolenoidVacuum Decreasing: 1v
6-7---Not Used---
8OR/RDHO2S-11 (B1 S1) HeaterPWM Signal: 0-12-0v
9---Not Used---
10WT/DGLDP Solenoid ControlPWM Signal: 0-12-0v
11YL/RDSpeed Control Power Supply12-14v
12DG/ORASD Relay Power (B+)12-14v
13OR/WTOverdrive Off Switch SenseSwitch Off: 12v, On: 1v
14ORLDP Switch Sense SignalLDP Switch Closed: 0v
15PK/YLBattery Temperature SensorAt 86°F: 1.96v
16VT/TNHO2S-21 (B2 S1) HeaterPWM Signal: 0-12-0v
17-18---Not Used---
19BRFuel Pump Relay ControlRelay Off: 12v, On: 1v
20PK/BKEVAP Purge Solenoid ControlPWM Signal: 0-12-0v
21---Not Used---
22DBA/C Pressure Switch SignalA/C On: 0.451-4.850v
23LG/GYA/C Select SignalA/C Off: 12v, On: 1v
24WT/PKBrake Switch Sense SignalBrake Off: 0v, On: 12v
25WT/DBGenerator Field Source12-14v
26LB/BKFuel Level Sensor SignalFull: 0.56v, 1/2 full: 2.5v
27PKSCI Transmit0v
28WT/BKCCD Bus (-)  
29LGSCI Receive5v
30VT/BRCCD Bus (+)Digital Signals: 0-5-0v
31---Not Used---
32WT/LGSpeed Control Set Switch SignalS/C & Set Switch On: 3.8v



Click image to see an enlarged view

Fig.

2001-03 RAM Van 5.9L VIN Z (A/T) White 'C2' Connector
PCM Pin #Wire ColorCircuit Description (32-Pin)Value at Hot Idle
1GY/BKTransmission Temperature Sensor SignalAt 200°F: 2.40v
2VTInjector 7 Driver1-4 ms
3, 9, 14, 17-20---Not Used---
4WT/DBInjector 1 Driver1-4 ms
5YL/WTInjector 3 Driver1-4 ms
6GYInjector 5 Driver1-4 ms
7---Not Used---
8VT/BKGovernor Pressure SolenoidPWM Signal: 0-12-0v
10DG/WTGenerator Field ControlDigital Signals: 0-12-0v
11OR/BKTCC Solenoid ControlAt Cruise w/TCC On: 1v
12BR/DBInjector 6 Driver1-4 ms
13GY/LBInjector 8 Driver1-4 ms
15TNInjector 2 Driver1-4 ms
16LB/BRInjector 4 Driver1-4 ms
21BR3-4 Shift Solenoid ControlCruise w/solenoid On: 1v
22---Not Used---
23GY/YLEngine Oil Pressure Sensor1.6v at 24 psi
24---Not Used---
25DBOSS Sensor (-) SignalMoving: AC pulse signals
26---Not Used---
27WT/ORVehicle Speed SignalDigital Signal
28LG/RDOSS Sensor (+) SignalMoving: AC pulse signals
29LG/RDGovernor Pressure Sensor0.58v
30PKTransmission Relay ControlRelay Off: 12v, On: 1v
31VT/WT5-Volt Supply4.9-5.1v
32---Not Used---
2003 Pickup & Van 8.0L VIN W 'C1' Black Connector
PCM Pin #Wire ColorCircuit Description (32-Pin)Value at Hot Idle
1YL/GYCoil 4 Driver Control5°, 55 mph: 8° dwell
2LG/BKIgnition Switch Output (Run-Start)12-14v
3RD/BKCoil 3 Driver Control5°, 55 mph: 8° dwell
4BK/LBSensor Ground  
5DG/GYCoil 5 Driver Control5°, 55 mph: 8° dwell
6BR/YLPNP Switch Sense SignalIn P/N: 0v, Others: 5v
7BK/GYCoil 1 Driver Control5°, 55 mph: 8° dwell
8GY/BKCKP Sensor SignalDigital Signals: 0-5-0v
9DB/TNCoil 2 Driver Control5°, 55 mph: 8° dwell
10GY/RDIAC 3 Driver ControlPulse Signals
11YL/BKIAC 2 Driver ControlPulse Signals
12-14---Not Used---
15BK/RDIAT Sensor SignalAt 100°F: 1.83v
16TN/BKECT Sensor SignalAt 180°F: 2.80v
17OR5-Volt Supply4.9-5.1v
18TN/YLCMP Sensor SignalDigital Signals: 0-5-0v
19VT/BKIAC 4 Driver ControlPulse Signals
20BR/WTIAC 1 Driver ControlPulse Signals
21---Not Used---
22RD/WTKeep Alive Power (B+)12-14v
23OR/DBTP Sensor Signal0.6-1.0v
24BK/DGHO2S-11 (B1 S1) Signal0.1-1.1v
25TN/WTHO2S-12 (B1 S2) Signal0.1-1.1v
26LG/RDHO2S-21 (B2 S1) Signal (California)0.1-1.1v
27OR/RDMAP Sensor Signal1.5-1.6v
28---Not Used---
29TN/WTHO2S-22 (B2 S2) Signal (California)0.1-1.1v
30---Not Used---
31BK/TNPower Ground  
32BK/TNPower Ground  



Click image to see an enlarged view

Fig.

2003 RAM Pickup & Van 8.0L VIN W 'C2' White Connector
PCM Pin #Wire ColorCircuit Description (32-Pin)Value at Hot Idle
1VTTransmission Temperature Sensor SignalAt 200°F: 2.40v
2VT/TNInjector 7 Driver1-4 ms
3TNInjector 9 Driver1-4 ms
4WT/DBInjector 1 Driver1-4 ms
5YL/WTInjector 3 Driver1-4 ms
6GYInjector 5 Driver1-4 ms
7---Not Used---
8VT/WTGovernor Pressure SolenoidPWM Signal: 0-12-0v
9---Not Used---
10DGGenerator Field ControlDigital Signals: 0-12-0v
11OR/BKTCC Solenoid ControlAt Cruise w/TCC On: 1v
12BR/DBInjector 6 Driver1-4 ms
13GY/LBInjector 8 Driver1-4 ms
14WT/DBInjector 10 Driver1-4 ms
15TNInjector 2 Driver1-4 ms
16LB/BRInjector 4 Driver1-4 ms
17DB/YLCondenser Fan Relay ControlRelay Off: 12v, On: 1v
18-20---Not Used---
21LB/BR3-4 Shift Solenoid ControlSolenoid Off: 12v, On: 1v
22---Not Used---
23GY/YLOil Pressure Sensor1.6v at 24 psi
24---Not Used---
25DB/BKOSS Sensor (-) SignalMoving: AC pulse signals
26---Not Used---
27WT/ORVehicle Speed SignalDigital Signals
28LG/WTOSS Sensor (+) SignalMoving: AC pulse signals
29LG/RDGovernor Pressure Sensor0.58v
30PKTransmission Relay ControlRelay Off: 12v, On: 1v
31WT5-Volt Supply4.9-5.1v
32---Not Used---



Click image to see an enlarged view

Fig.

2003 RAM Pickup & Van 8.0L VIN W 'C3' Gray Connector
PCM Pin #Wire ColorCircuit Description (32-Pin)Value at Hot Idle
1ORA/C Clutch Relay ControlRelay Off: 12v, On: 1v
2---Not Used---
3DB/YLASD Relay ControlRelay Off: 12v, On: 1v
4TN/RDSpeed Control Vacuum SolenoidVacuum Increasing: 1v
5LG/RDSpeed Control Vent SolenoidVacuum Decreasing: 1v
6-7---Not Used---
8BR/VTHO2S-11 Heater Control (California)Heater Off: 12v, On: 1v
9DB/ORHO2S-12 Heater Relay (California)Relay Off: 12v, On: 1v
10WT/ORLDP Solenoid ControlPWM Signal: 0-12-0v
11YL/RDSpeed Control Power Supply12-14v
12DG/ORASD Relay Output (B+)12-14v
13---Not Used---
14ORLDP Switch Sense SignalLDP Switch Closed: 0v
15PK/YLBattery Temperature SensorAt 86°F: 1.96v
16BR/WTHO2S-21 Heater Control (Except California)Heater Off: 12v, On: 1v
17-18---Not Used---
19BRFuel Pump Relay ControlRelay Off: 12v, On: 1v
20PK/BKEVAP Purge Solenoid ControlPWM Signal: 0-12-0v
21-23---Not Used---
24WT/PKBrake Switch SenseBrake Off: 0v, On: 12v
25WT/ORGenerator Field Source12-14v
26LB/BKFuel Level Sensor SignalFull: 0.56v, 1/2 full: 2.5v
27PKSCI Transmit0v
28---Not Used---
29LGSCI Receive5v
30VT/BRPCI Data Bus (J1850)Digital Signals: 0-7-0v
31---Not Used---
32RD/LGSpeed Control Set Switch SignalS/C & Set Switch On: 3.8v



Click image to see an enlarged view

Fig.

Standard Colors And Abbreviations
AbbreviationColorAbbreviationColorAbbreviationColor
BKBlackGYGrayRDRed
BLBlueGNGreenTNTan
BRBrownLGLight GreenVTViolet
DBDark BlueOROrangeWTWhite
DGDark GreenPKPinkYLYellow
AbbreviationColorAbbreviationColorAbbreviationColor
BKBlackGYGrayRDRed
BLBlueGNGreenTNTan
BRBrownLGLight GreenVTViolet
DBDark BlueOROrangeWTWhite
DGDark GreenPKPinkYLYellow
Vehicle Does Not Fill

Test Chart

CONDITIONPOSSIBLE CAUSESCORRECTION
Pre-Mature Nozzle Shut-OffDefective fuel tank assembly components.Fill tube improperly installed (sump)
Fill tube hose pinched.
Check valve stuck shut.
Control valve stuck shut.
Defective vapor/vent components.Vent line from control valve to canister pinched.
Vent line from canister to vent filter pinched.
Canister vent valve failure (requires double failure, plugged to NVLD and atmosphere).
Leak detection pump failed closed.
Leak detection pump filter plugged.
On-Board diagnostics evaporative system leak test just conducted.Canister vent valve vent plugged to atmosphere.
Engine still running when attempting to fill (System designed not to fill).
Defective fill nozzle.Try another nozzle.
Fuel Spits Out Of Filler Tube.During fill.See Pre-Mature Shut-Off.
  At conclusion of fill.Defective fuel handling component. (Check valve stuck open).
Defective vapor/vent handling component.
Defective fill nozzle.

Test Chart

CONDITIONPOSSIBLE CAUSESCORRECTION
Pre-Mature Nozzle Shut-OffDefective fuel tank assembly components.Fill tube improperly installed (sump)
Fill tube hose pinched.
Check valve stuck shut.
Control valve stuck shut.
Defective vapor/vent components.Vent line from control valve to canister pinched.
Vent line from canister to vent filter pinched.
Canister vent valve failure (requires double failure, plugged to NVLD and atmosphere).
Leak detection pump failed closed.
Leak detection pump filter plugged.
On-Board diagnostics evaporative system leak test just conducted.Canister vent valve vent plugged to atmosphere.
Engine still running when attempting to fill (System designed not to fill).
Defective fill nozzle.Try another nozzle.
Fuel Spits Out Of Filler Tube.During fill.See Pre-Mature Shut-Off.
  At conclusion of fill.Defective fuel handling component. (Check valve stuck open).
Defective vapor/vent handling component.
Defective fill nozzle.

Symptom Diagnosis Tests



Test 1: No Start, Hard Start Condition

NOTE
If there is no spark output or fuel pressure available, check for a failed fuel pump relay, no power to the PCM, or loss of the ignition reference signal to the PCM.


NOTE
If there is no spark output or fuel pressure available, check for a failed fuel pump relay, no power to the PCM, or loss of the ignition reference signal to the PCM.

Preliminary Checks

Prior to starting this symptom test routine, inspect these underhood items:

  1. Check battery charge and condition, starter current draw.
  2.  
  3. Verify the starter relay operation and that the engine cranks (turns over).
  4.  
  5. Verify the check engine light (MIL) operation - if it does not activate, check the PCM power and ground circuits, and check for 5v supply at the MAP or TP sensor.
  6.  
  7. Check Air Intake system for restrictions (inspect air inlet tubes, air filter for dirt, etc.).
  8.  
  9. Check the status of the Smart Key Immobilizer System (SKIM) with the Scan Tool.
  10.  

Test 1 Chart

StepActionYesNo
1Step Description: No Start Condition Only · Check battery cables, state of charge. If the engine does not rotate, inspect for a locked engine (hydrostatic lockup condition). Does the engine crank normally-Go to Step 2.Repair the fault in the battery, starter, or Base Engine. Retest for the symptom when all repairs are done.
2Step Description: Check the Fuel System Verify that the pump operates at key on. Check the fuel pump relay operation. If the relay does not operate, check for blown fuse. Inspect pump for a leak-down condition Test fuel pressure, volume and quality. Test the operation of the fuel regulator. Are there any faults in the Fuel system- Make needed repairs. Go to Step 3.
3Step Description: Check the Ignition System Inspect ignition secondary components for damage (look for rotor "punch-through"). Inspect the coils for signs of spark leakage at coil towers or primary connections. Check the spark output with a spark tester. Test Ignition system with an engine analyzer. Are there any faults in the Ignition system- Make repairs to the Ignition system. Then retest the symptom. Go to Step 4.
4Step Description: Check the Exhaust System Check Exhaust system for leaks or damage. Check the Exhaust system for a restriction using the Vacuum or Pressure Gauge Test (e.g., exhaust backpressure reading should not exceed 1.5 psi at cruise speeds). Are there any faults in the Exhaust system- Make repairs to the Exhaust system. Then retest the symptom. Go to Step 5.
5Step Description: Check the MAP Sensor Disconnect the MAP sensor and attempt to start the engine. Does the engine start and run normally-Replace the MAP sensor. Retest for the symptom when repairs are completed.Go to Step 6.

Test 1: No Start, Hard Start Condition (Continued)

Test 1 Chart (Continued)

StepAction (Hard Start Only)YesNo
6Step Description: Check for a Hot Engine Check for signs of an engine overheating condition related to a Hard Start Symptom. Does the engine appear to be overheated-Make the repairs to correct the hot engine and then retest for the symptom when done.Go to Step 7.
7Step Description: Check ECT Sensor PID Connect a Scan Tool and turn the key to on. Read the ECT sensor (compare to chart). Has the ECT sensor shifted out of range-Replace the ECT sensor. Then retest for the symptom when all repairs are completed.Go to Step 8.
8Step Description: Check the PCV System Inspect the PCV system components for broken parts or loose connections. Test the operation of the PCV valve. Are there any faults in the PCV system-Repair the PCV system. Refer to the PCV system tests. Retest the symptom when all repairs are done.Go to Step 9.
9Step Description: Check the EVAP System Inspect for damaged or disconnected EVAP system components. Inspect for a fuel saturated charcoal canister. Are there any faults in the EVAP system-Refer to the EVAP system tests in this manual. Retest for the symptom when all repairs are completed.Go to Step 10.
10Step Description: Test the Base Engine Check the engine compression. Test valve timing and timing chain condition. Check for a worn camshaft or valve train. Check for any large intake manifold leaks. Are there any faults in the Base Engine-Repair the Base Engine. Refer to the Base Engine Tests. Retest symptom when done.Return to Step 2 to repeat the test steps in this series to locate and repair the "No Start, Hard Start" condition.

Prior to starting this symptom test routine, inspect these underhood items:

  1. Check battery charge and condition, starter current draw.
  2.  
  3. Verify the starter relay operation and that the engine cranks (turns over).
  4.  
  5. Verify the check engine light (MIL) operation - if it does not activate, check the PCM power and ground circuits, and check for 5v supply at the MAP or TP sensor.
  6.  
  7. Check Air Intake system for restrictions (inspect air inlet tubes, air filter for dirt, etc.).
  8.  
  9. Check the status of the Smart Key Immobilizer System (SKIM) with the Scan Tool.
  10.  

Test 1 Chart

StepActionYesNo
1Step Description: No Start Condition Only Check battery cables, state of charge. If the engine does not rotate, inspect for a locked engine (hydrostatic lockup condition). Does the engine crank normally-Go to Step 2.Repair the fault in the battery, starter, or Base Engine. Retest for the symptom when all repairs are done.
2Step Description: Check the Fuel System Verify that the pump operates at key on. Check the fuel pump relay operation. If the relay does not operate, check for blown fuse. Inspect pump for a leak-down condition Test fuel pressure, volume and quality. Test the operation of the fuel regulator. Are there any faults in the Fuel system- Make needed repairs. Go to Step 3.
3Step Description: Check the Ignition System Inspect ignition secondary components for damage (look for rotor "punch-through"). Inspect the coils for signs of spark leakage at coil towers or primary connections. Check the spark output with a spark tester. Test Ignition system with an engine analyzer. Are there any faults in the Ignition system- Make repairs to the Ignition system. Then retest the symptom. Go to Step 4.
4Step Description: Check the Exhaust System Check Exhaust system for leaks or damage. Check the Exhaust system for a restriction using the Vacuum or Pressure Gauge Test (e.g., exhaust backpressure reading should not exceed 1.5 psi at cruise speeds). Are there any faults in the Exhaust system- Make repairs to the Exhaust system. Then retest the symptom. Go to Step 5.
5Step Description: Check the MAP Sensor Disconnect the MAP sensor and attempt to start the engine. Does the engine start and run normally-Replace the MAP sensor. Retest for the symptom when repairs are completed.Go to Step 6.

Test 1: No Start, Hard Start Condition (Continued)

Test 1 Chart (Continued)

StepAction (Hard Start Only)YesNo
6Step Description: Check for a Hot Engine Check for signs of an engine overheating condition related to a Hard Start Symptom. Does the engine appear to be overheated-Make the repairs to correct the hot engine and then retest for the symptom when done.Go to Step 7.
7Step Description: Check ECT Sensor PID Connect a Scan Tool and turn the key to on. Read the ECT sensor (compare to chart). Has the ECT sensor shifted out of range-Replace the ECT sensor. Then retest for the symptom when all repairs are completed.Go to Step 8.
8Step Description: Check the PCV System Inspect the PCV system components for broken parts or loose connections. Test the operation of the PCV valve. Are there any faults in the PCV system-Repair the PCV system. Refer to the PCV system tests. Retest the symptom when all repairs are done.Go to Step 9.
9Step Description: Check the EVAP System Inspect for damaged or disconnected EVAP system components. Inspect for a fuel saturated charcoal canister. Are there any faults in the EVAP system-Refer to the EVAP system tests in this manual. Retest for the symptom when all repairs are completed.Go to Step 10.
10Step Description: Test the Base Engine Check the engine compression. Test valve timing and timing chain condition. Check for a worn camshaft or valve train. Check for any large intake manifold leaks. Are there any faults in the Base Engine-Repair the Base Engine. Refer to the Base Engine Tests. Retest symptom when done.Return to Step 2 to repeat the test steps in this series to locate and repair the "No Start, Hard Start" condition.
Test 2 Chart (Continued)
StepActionYesNo
8Step Description: Check the PCV System Inspect the PCV system components for broken parts or loose connections. Test the operation of the PCV valve. Were any faults found in the PCV system-Make repairs to the PCV system. Refer to the PCV system tests. Then retest for the condition.Go to Step 9.
9Step Description: Check the EVAP System Inspect for damaged or disconnected EVAP system components or a saturated canister. Were any faults found in the EVAP system-Make repairs to EVAP system (use the EVAP tests in this manual). Retest for the condition.Go to Step 10.
10Step Description: Check the Base Engine Test the engine compression. Test valve timing and timing chain condition. Check for a worn camshaft or valve train. Check for any large intake manifold leaks. Were any faults found in the Base Engine-Make repairs as needed to the Base Engine. Refer to the Base Engine tests. Then retest for the condition when repairs are completed.Go to Step 2 and repeat the tests from the beginning to locate and repair the cause of the "Rough, Low or High Idle Speed" condition.
StepActionYesNo
8Step Description: Check the PCV System Inspect the PCV system components for broken parts or loose connections. Test the operation of the PCV valve. Were any faults found in the PCV system-Make repairs to the PCV system. Refer to the PCV system tests. Then retest for the condition.Go to Step 9.
9Step Description: Check the EVAP System Inspect for damaged or disconnected EVAP system components or a saturated canister. Were any faults found in the EVAP system-Make repairs to EVAP system (use the EVAP tests in this manual). Retest for the condition.Go to Step 10.
10Step Description: Check the Base Engine Test the engine compression. Test valve timing and timing chain condition. Check for a worn camshaft or valve train. Check for any large intake manifold leaks. Were any faults found in the Base Engine-Make repairs as needed to the Base Engine. Refer to the Base Engine tests. Then retest for the condition when repairs are completed.Go to Step 2 and repeat the tests from the beginning to locate and repair the cause of the "Rough, Low or High Idle Speed" condition.
Test 3: Runs Rough Condition

NOTE
If the vehicle has a rough idle and the base timing, idle speed and the IAC (or AIS) motor operates properly, check the engine for excessive carbon buildup.


NOTE
If the vehicle has a rough idle and the base timing, idle speed and the IAC (or AIS) motor operates properly, check the engine for excessive carbon buildup.

Preliminary Checks

Prior to starting this symptom test routine, inspect these underhood items:

  1. All related vacuum lines for proper routing and integrity.
  2.  
  3. All related electrical connectors and wiring harnesses for faults (Wiggle Test).
  4.  
  5. Check the throttle linkage for a sticking or binding condition.
  6.  
  7. Air Intake system for restrictions (air inlet tubes, dirty air filter, etc.).
  8.  
  9. Search for any technical service bulletins related to this symptom.
  10.  
  11. Turn the key to off. Unplug the MAP sensor connection and restart the engine to recheck for the idle concern. If the condition is gone, replace the MAP sensor.
  12.  

Test 2: Rough, Low or High Idle Speed Condition (Continued)

Test 2 Chart

StepActionYesNo
1Step Description: Verify the rough idle or stall Does the engine have a warm engine rough idle, low idle or high idle condition in P or N-Go to Step 2.Fault is intermittent. Return to the Symptom List and select another fault.
2Step Description: Verify idle speed & timing Verify the base timing is within specifications Verify that the base idle speed is set properly Are the timing and idle speed set properly-Go to Step 3.Set the base idle speed and timing to the specifications and then retest for the symptom.
3Step Description: Check AIS / IAC Operation Check the AIS or IAC motor operation Inspect the AIS/IAC housing in throttle body for restricted passages. Clean as needed. Set the parking brake, block the drive wheels and turn the A/C off. Install the Scan Tool. IAC Motor Tester - Turn the key off and then connect the IAC tester to the IAC valve. Start the engine and use the IAC tester to extend and retract the IAC valve. ATM Test - Start the engine. Use the tool to change the speed from min-idle to 1500 rpm. Did the idle speed change as commanded-Install an Aftermarket Noid light and check the operation of the PCM and AIS or IAC motor circuits. Check the motor for signs of open or shorted circuits. Replace the IAC motor or PCM as needed or make repairs to the IAC motor wiring. If all are okay, go to Step 4.If the AIS/IAC motor passages are clean and engine speed did not change as described when the AIS/IAC motor was extended and retracted, replace the AIS/IAC motor. Then retest for the condition.
4Step Description: Check/compare PID values Connect Scan Tool & turn off all accessories. Start the engine and allow it to fully warmup. Monitor all related PIDs on the Scan Tool. Verify the P/N switch input in gear and Park. Check the O2S operation with a Lab Scope. Are all PIDs within normal range-Go to Step 5. Note: An IAC motor count of over 80 indicates the pintle is extended and an IAC count of (0) indicates the pintle is retracted.One or more of the PIDs are out of range when compared to "known good" values. Make repairs to the system that is out of range, then retest for the symptom.
5Step Description: Check the Ignition System Inspect the coils for signs of spark leakage at coil towers or primary connections. Check the spark output with a spark tester. Test Ignition system with an engine analyzer. Were any faults found in the Ignition system- Make repairs as needed Go to Step 6.
6Step Description: Check the Fuel System Inspect the Fuel delivery system for leaks. Test the fuel pressure, quality and volume. Test the operation of the pressure regulator. Were any faults found in the Fuel system- Make repairs as needed Go to Step 7.
7Step Description: Check the Exhaust System Check Exhaust system for leaks or damage. Check the Exhaust system for a restriction using the Vacuum or Pressure Gauge Test (e.g., exhaust backpressure reading should not exceed 1.5 psi at cruise speeds). Were any faults found in Exhaust System- Make repairs to the Exhaust system. Then retest the symptom. Go to Step 8.

Rough, Low or High Idle Speed Condition (Continued)

Prior to starting this symptom test routine, inspect these underhood items:

  1. All related vacuum lines for proper routing and integrity
  2.  
  3. Air Intake system for restrictions (air inlet tubes, dirty air filter, etc.)
  4.  
  5. Search for any technical service bulletins related to this symptom.
  6.  

Test 3 Chart

StepActionYesNo
1Step Description: Verify engine runs rough Start the engine and allow it to idle in P or N. Does the engine run rough when warm in Park or Neutral position-Check for any stored codes. If codes are set, repair codes and retest. If no codes are set, go to Step 3.Go to Step 2.
2Step Description: Condition does not exist! Inspect various underhood items that could cause an intermittent Runs Rough condition (i.e., dirt in the throttle body, vacuum leaks, IAC motor connections, etc.). Were any problems located in this step-Correct the problems. Do a PCM reset and engine "idle relearn" procedure. Then verify the "runs rough" condition is repaired.The problem is not present at this time. It may be an intermittent problem.
3Step Description: Check/compare PID values Connect a Scan Tool to the test connector. Turn off all accessories. Start the engine and allow it to fully warmup. Monitor all related PIDs on the Scan Tool. Were all PIDs within their normal range-Go to Step 4. Note: The IAC motor should read from 5-50 counts. Check the LONGFT reading for a large shift into the negative range (due to a rich condition).One or more of the PIDs are out of range when compared to "known good" values. Make repairs to the system that is out of range, then retest for the symptom.

Test 3: Runs Rough Condition (Continued)

Test 3 Chart (Continued)

StepActionYesNo
4Step Description: Check the Ignition System Inspect the coils for signs of spark leakage at coil towers or primary connections. Check the spark output with a spark tester. Test Ignition system with an engine analyzer. Were any faults found in the Ignition system- Make repairs as needed Go to Step 5.
5Step Description: Check the Fuel System Inspect the Fuel delivery system for leaks. Test the fuel pressure, quality and volume. Test the operation of the pressure regulator. Were any faults found in the Fuel system- Make repairs as needed Go to Step 6.
6Step Description: Check the Exhaust System Check Exhaust system for leaks or damage. Check the Exhaust system for a restriction using the Vacuum or Pressure Gauge Test (e.g., exhaust backpressure reading should not exceed 1.5 psi at cruise speeds). Were any faults found in Exhaust System- Make repairs to the Exhaust system. Then retest the symptom. Go to Step 7.
7Step Description: Check the PCV System Inspect the PCV system components for broken parts or loose connections. Test the operation of the PCV valve. Were any faults found in the PCV system-Make repairs to the PCV system. Refer to the PCV system tests. Then retest for the condition.Go to Step 9.
8Step Description: Check the EVAP System Inspect for damaged or disconnected EVAP system components or a saturated canister. Were any faults found in the EVAP system-Make repairs to EVAP system (use the EVAP tests in this manual). Retest for the condition.Go to Step 10.
9Step Description: Check Engine Condition Test the engine compression. Test valve timing and timing chain condition. Check for a worn camshaft or valve train. Check for any large intake manifold leaks. Were any faults found in the Base Engine-Make repairs as needed to the Base Engine. Refer to the Base Engine tests. Then retest for the condition when repairs are completed.Return to Step 2 and repeat the tests from the beginning to locate and repair the cause of the "Runs Rough" condition.

Example EVAP System Graphic

Click image to see an enlarged view

Fig.

Prior to starting this symptom test routine, inspect these underhood items:

  1. All related vacuum lines for proper routing and integrity.
  2.  
  3. All related electrical connectors and wiring harnesses for faults (Wiggle Test).
  4.  
  5. Check the throttle linkage for a sticking or binding condition.
  6.  
  7. Air Intake system for restrictions (air inlet tubes, dirty air filter, etc.).
  8.  
  9. Search for any technical service bulletins related to this symptom.
  10.  
  11. Turn the key to off. Unplug the MAP sensor connection and restart the engine to recheck for the idle concern. If the condition is gone, replace the MAP sensor.
  12.  

Test 2: Rough, Low or High Idle Speed Condition (Continued)

Test 2 Chart

StepActionYesNo
1Step Description: Verify the rough idle or stall Does the engine have a warm engine rough idle, low idle or high idle condition in P or N-Go to Step 2.Fault is intermittent. Return to the Symptom List and select another fault.
2Step Description: Verify idle speed & timing Verify the base timing is within specifications Verify that the base idle speed is set properly Are the timing and idle speed set properly-Go to Step 3.Set the base idle speed and timing to the specifications and then retest for the symptom.
3Step Description: Check AIS / IAC Operation Check the AIS or IAC motor operation Inspect the AIS/IAC housing in throttle body for restricted passages. Clean as needed. Set the parking brake, block the drive wheels and turn the A/C off. Install the Scan Tool. IAC Motor Tester - Turn the key off and then connect the IAC tester to the IAC valve. Start the engine and use the IAC tester to extend and retract the IAC valve. ATM Test - Start the engine. Use the tool to change the speed from min-idle to 1500 rpm. Did the idle speed change as commanded-Install an Aftermarket Noid light and check the operation of the PCM and AIS or IAC motor circuits. Check the motor for signs of open or shorted circuits. Replace the IAC motor or PCM as needed or make repairs to the IAC motor wiring. If all are okay, go to Step 4.If the AIS/IAC motor passages are clean and engine speed did not change as described when the AIS/IAC motor was extended and retracted, replace the AIS/IAC motor. Then retest for the condition.
4Step Description: Check/compare PID values Connect Scan Tool & turn off all accessories. Start the engine and allow it to fully warmup. Monitor all related PIDs on the Scan Tool. Verify the P/N switch input in gear and Park. Check the O2S operation with a Lab Scope. Are all PIDs within normal range-Go to Step 5. Note: An IAC motor count of over 80 indicates the pintle is extended and an IAC count of (0) indicates the pintle is retracted.One or more of the PIDs are out of range when compared to "known good" values. Make repairs to the system that is out of range, then retest for the symptom.
5Step Description: Check the Ignition System Inspect the coils for signs of spark leakage at coil towers or primary connections. Check the spark output with a spark tester. Test Ignition system with an engine analyzer. Were any faults found in the Ignition system- Make repairs as needed Go to Step 6.
6Step Description: Check the Fuel System Inspect the Fuel delivery system for leaks. Test the fuel pressure, quality and volume. Test the operation of the pressure regulator. Were any faults found in the Fuel system- Make repairs as needed Go to Step 7.
7Step Description: Check the Exhaust System Check Exhaust system for leaks or damage. Check the Exhaust system for a restriction using the Vacuum or Pressure Gauge Test (e.g., exhaust backpressure reading should not exceed 1.5 psi at cruise speeds). Were any faults found in Exhaust System- Make repairs to the Exhaust system. Then retest the symptom. Go to Step 8.

Rough, Low or High Idle Speed Condition (Continued)

Prior to starting this symptom test routine, inspect these underhood items:

  1. All related vacuum lines for proper routing and integrity
  2.  
  3. Air Intake system for restrictions (air inlet tubes, dirty air filter, etc.)
  4.  
  5. Search for any technical service bulletins related to this symptom.
  6.  

Test 3 Chart

StepActionYesNo
1Step Description: Verify engine runs rough Start the engine and allow it to idle in P or N. Does the engine run rough when warm in Park or Neutral position-Check for any stored codes. If codes are set, repair codes and retest. If no codes are set, go to Step 3.Go to Step 2.
2Step Description: Condition does not exist! Inspect various underhood items that could cause an intermittent Runs Rough condition (i.e., dirt in the throttle body, vacuum leaks, IAC motor connections, etc.). Were any problems located in this step-Correct the problems. Do a PCM reset and engine "idle relearn" procedure. Then verify the "runs rough" condition is repaired.The problem is not present at this time. It may be an intermittent problem.
3Step Description: Check/compare PID values Connect a Scan Tool to the test connector. Turn off all accessories. Start the engine and allow it to fully warmup. Monitor all related PIDs on the Scan Tool. Were all PIDs within their normal range-Go to Step 4. Note: The IAC motor should read from 5-50 counts. Check the LONGFT reading for a large shift into the negative range (due to a rich condition).One or more of the PIDs are out of range when compared to "known good" values. Make repairs to the system that is out of range, then retest for the symptom.

Test 3: Runs Rough Condition (Continued)

Test 3 Chart (Continued)

StepActionYesNo
4Step Description: Check the Ignition System Inspect the coils for signs of spark leakage at coil towers or primary connections. Check the spark output with a spark tester. Test Ignition system with an engine analyzer. Were any faults found in the Ignition system- Make repairs as needed Go to Step 5.
5Step Description: Check the Fuel System Inspect the Fuel delivery system for leaks. Test the fuel pressure, quality and volume. Test the operation of the pressure regulator. Were any faults found in the Fuel system- Make repairs as needed Go to Step 6.
6Step Description: Check the Exhaust System Check Exhaust system for leaks or damage. Check the Exhaust system for a restriction using the Vacuum or Pressure Gauge Test (e.g., exhaust backpressure reading should not exceed 1.5 psi at cruise speeds). Were any faults found in Exhaust System- Make repairs to the Exhaust system. Then retest the symptom. Go to Step 7.
7Step Description: Check the PCV System Inspect the PCV system components for broken parts or loose connections. Test the operation of the PCV valve. Were any faults found in the PCV system-Make repairs to the PCV system. Refer to the PCV system tests. Then retest for the condition.Go to Step 9.
8Step Description: Check the EVAP System Inspect for damaged or disconnected EVAP system components or a saturated canister. Were any faults found in the EVAP system-Make repairs to EVAP system (use the EVAP tests in this manual). Retest for the condition.Go to Step 10.
9Step Description: Check Engine Condition Test the engine compression. Test valve timing and timing chain condition. Check for a worn camshaft or valve train. Check for any large intake manifold leaks. Were any faults found in the Base Engine-Make repairs as needed to the Base Engine. Refer to the Base Engine tests. Then retest for the condition when repairs are completed.Return to Step 2 and repeat the tests from the beginning to locate and repair the cause of the "Runs Rough" condition.

Example EVAP System Graphic

Click image to see an enlarged view

Fig.

 
label.common.footer.alt.autozoneLogo