Inspection Procedure 19

INSPECTION PROCEDURE 19: Surge.

COMMENT
- Defective ignition system, abnormal air/fuel ratio, the electronic control throttle valve system failed, etc. are suspected.

TROUBLESHOOTING HINTS (The most likely causes for this case:)
- Malfunction of the ignition system.
- Malfunction of air/fuel ratio control system.
- Malfunction of the electronic control throttle valve system.
- Malfunction of the EGR system.

DIAGNOSIS

Required Special Tools:
- MB991958: Scan Tool (M.U.T.-III Sub Assembly)
- MB991824: V.C.I.
- MB991827: USB Cable
- MB991910: Main Harness A

STEP 1. Using scan tool MB991958, read the diagnostic trouble code (DTC).

CAUTION: To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958.




1. Connect scan tool MB991958 to the data link connector.
2. Turn the ignition switch to the "ON" position.
3. Read the DTC.
4. Turn the ignition switch to the "ON" position.

Q: Is any DTC set?

YES: Refer to Diagnostic Trouble Code Chart. Diagnostic Trouble Code Descriptions

NO: Go to Step 2.

STEP 2. Using scan tool MB991958, check actuator test items 1, 2, 3, 4, 5, 6: Injector.




1. Turn the ignition switch to the "ON" position.
2. Check following items in the actuator test. Refer to Actuator Test Reference Table. Actuator Test Reference Table
a. Item 1, 2, 3, 4, 5, 6: Injector.

3. Turn the ignition switch to the "ON" position.

Q: Are thy operating properly?

YES: Go to Step 3.

NO: Refer to DTC P0201, P0202, P0203, DTC P0204, P0205, P0206 - Injector Circuit.

STEP 3. Check the ignition timing.

Refer to On-vehicle Service - Ignition Timing Check.

Q: Is the ignition timing normal?

YES: Go to Step 4.

NO: Check that the crankshaft position sensor and timing belt cover are in the correct position. Then confirm that the malfunction symptom is eliminated.

STEP 4. Using scan tool MB991958, check data list.

CAUTION: To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958.




1. Connect scan tool MB991958 to the data link connector.
2. Turn the ignition switch to the "ON" position.
3. Check the following items in the data list. Refer to Data List Reference Table. Data List Reference Table & Normal Scan Data Values
a. Item 5: Intake Air Temperature Sensor.
b. Item 6: Engine Coolant Temperature Sensor.

4. Turn the ignition switch to the "LOCK" (OFF) position.

Q: Are they operating properly?

YES: Go to Step 5.

NO: Repair or replace it. Then confirm that the malfunction symptom is eliminated.

STEP 5. Measure the sensor output voltage at PCM connector B-22 by using power plant ECU check harness special tool MB991923.







1. Disconnect all PCM connectors. Connect the power plant ECU check harness special tool MB991923 between the separated connectors.
2. Start the engine and run at idle.




3. Measure the voltage between terminal No. 92 and ground.
- Warming up the engine. When the engine is 2,500 r/min, the output voltage should repeat 0.5 to 1.4 volts alternately.




4. Measure the voltage between terminal No. 91 and ground.
- Warming up the engine. When the engine is 2,500 r/min, the output voltage should repeat 0.5 to 1.4 volts alternately.

5. Turn the ignition switch to the "LOCK"(OFF) position.

Q: Is the measured voltage within the specified range?

YES: Go to Step 7.

NO: Go to Step 6.

STEP 6. Check the fuel pressure.

Q: Is the fuel pressure normal?

YES: Check the following items, and repair or replace the defective items.
a. Vacuum leak.
- Broken intake manifold gasket.
- Broken air intake hose.
- Broken vacuum hose.
- Positive crankcase ventilation valve does not operate.

b. Injector clogged.
Then confirm that the malfunction symptom is eliminated.

NO: Repair or replace it. Then confirm that the malfunction symptom is eliminated.

STEP 7. Check the fuel pressure.

Q: Is the fuel pressure normal?

YES: Check the following items, and repair or replace the defective items.
a. Check the ignition coil and spark plugs.
b. Check the EGR system.

Then confirm that the malfunction symptom is eliminated.

NO: Repair or replace it. Then confirm that the malfunction symptom is eliminated.