| 1 |
Was the "On-Board Diagnostic (OBDII) System Check" performed? |
- |
Go to Step 2 |
Go to On-Board Diagnostic (OBD-II) System Check |
| 2 |
- Perform a bulletin search.
- If a bulletin that addresses the symptom is found, correct the condition as instructed in the bulletin.
Was a bulletin found that addresses the symptom? |
- |
Go to Step 14 |
Go to Step 3 |
| 3 |
Was a visual/physical check performed? |
- |
Go to Step 4 |
Go to VISUAL/PHYSICAL CHECK |
| 4 |
Was the "Electric Throttle Control (ETC) System Check" performed? |
- |
Go to Step 5 |
Go to On-Board Diagnostic (OBD-II) System Check |
| 5 |
- Check the ECM grounds for clearness, tightness and proper routing. Refer to the ENGINE PERFORMANCE
in Electrical Diagnosis.
- If a problem is found, repair as necessary.
Was a problem found? |
- |
Verify repair |
Go to Step 6 |
| 6 |
Observe the long term fuel trim on the Tech 2.
Is the long term fuel trim significantly in the negative range (rich condition)? |
- |
Go to Step 7 |
Go to Step 8 |
| 7 |
- Check items that can cause the engine to run rich. Refer to Diagnostic Aids
in DTC P0172, P0172 Diagnostic Support.
- If a problem is found, repair as necessary.
Was a problem found? |
- |
Verify repair |
Go to Step 10 |
| 8 |
Is the long term fuel trim significantly in the positive range (lean condition)? |
- |
Go to Step 9 |
Go to Step 10 |
| 9 |
- Check items that can cause the engine to run lean. Refer to Diagnostic Aids
in DTC P0171, P0171 Diagnostic Support.
- If a problem is found, repair as necessary.
Was a problem found? |
- |
Verify repair |
Go to Step 10 |
| 10 |
- Check for incorrect idle speed. Ensure that the following conditions are present:
- The engine is fully warm.
- The accessories are "off".
- Using a Tech 2, monitor the Engine Speed.
Is the Engine Speed within the specified values? |
Desired Idle Speed |
Go to Step 12 |
Go to Step 11 |
| 11 |
- Visually/physically inspect for the following conditions:
- Restricted air intake system. Check for a possible collapsed air intake duct, restricted air filter element, or foreign objects blocking The air intake system.
- Large vacuum leak. Check for a condition that causes a large vacuum leak, such as an incorrectly installed or faulty PCV valve or brake booster hose disconnected.
- If a problem is found, repair as necessary.
Was a problem found? |
- |
Verify repair |
Go to Step 9 |
| 12 |
Check the injector connections. If any of the injectors are connected to an incorrect cylinder, correct as necessary.
Was a problem found? |
- |
Verify repair |
Go to Step 13 |
| 13 |
- Perform the "Injector Coil/Balance Test" in
.
- If a problem is found, repair as necessary.
Was a problem found? |
- |
Verify repair |
Go to Step 14 |
| 14 |
- Check for fuel pressure. Refer to Fuel System Check (High Pressure Line)
or Fuel System Check (Low Pressure Line)
.
- If a problem is found, repair as necessary.
Was a problem found? |
- |
Verify repair |
Go to Step 15 |
| 15 |
- Check for proper ignition voltage output with spark tester J 26792 (ST-125). Refer to IGNITION SYSTEM
for the procedure.
- If a problem is found, repair as necessary.
Was a problem found? |
- |
Verify repair |
Go to Step 16 |
| 16 |
- Remove spark plugs. Check for wet plugs, cracks, wear, improper gap, burned electrodes, or heavy deposits. Refer to IGNITION SYSTEM
.
NOTE:
If spark plugs are gas or oil fouled, the cause of the fouling must be determined before replacing the spark plugs.
- If a problem is found, repair as necessary.
Was a problem found? |
- |
Verify repair |
Go to Step 17 |
| 17 |
- Check for a loose ignition coil ground circuit.
- If a problem is found, repair as necessary.
Was a problem found? |
- |
Verify repair |
Go to Step 18 |
| 18 |
- Check ignition coils for cracks or carbon tracking.
- If a problem is found, repair as necessary.
Was a problem found? |
- |
Verify repair |
Go to Step 19 |
| 19 |
Using a Tech 2, monitor the TP 1, 2 angle with the engine idling.
Is the TP angle at the specified value and steady? |
8 - 10% |
Go to Step 20 |
Refer to DTC P0123
for further diagnosis |
| 20 |
- Check the PCV valve for proper operation. Refer to General Description (Positive Crankcase Ventilation (PCV) System)
.
- If a problem is found, repair as necessary.
Was a problem found? |
- |
Verify repair |
Go to Step 21 |
| 21 |
- Check the transmission range switch circuit. Use a Tech 2 and be sure the Tech 2 indicates that the vehicle is in drive with the gear selector in drive or overdrive.
- If a problem is found, diagnose and repair the transmission range switch as necessary (refer to TRANSMISSION CONTROL SYSTEM
).
Was a problem found? |
- |
Verify repair |
Go to Step 22 |
| 22 |
- Check the following engine mechanical items. Refer to ENGINE MECHANICAL (6VE1-DI - 3.5L)
for diagnosis procedures:
- Low compression
- Sticking or leaking valves
- Worn camshaft lobes
- Camshaft drive belt slipped or stripped
- Incorrect valve timing
- Worn rocker arms
- Broken valve springs
- If a problem is found, repair as necessary.
Was a problem found? |
- |
Verify repair |
Go to Step 23 |
| 23 |
- Check for faulty motor mounts. Refer to ENGINE MECHANICAL (6VE1-DI - 3.5L)
for inspection of mounts.
- If a problem is found, repair as necessary.
Was a problem found? |
- |
Verify repair |
Go to Step 24 |
| 24 |
- Review all diagnostic procedures within this table.
- If all procedures have been completed and no malfunctions have been found, review/inspect the following:
- Visual/physical inspection
- Tech 2 data
- Freeze Frame data/Failure Records butter
- All electrical connections within a suspected circuit and/or system
- If a problem is found, repair as necessary.
Was a problem found? |
- |
Verify repair |
- |