DTC Diagnosis Procedure

1. Start engine and run it at idle.
2. Listen for an exhaust gas leak before three way catalyst (manifold).

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   Is exhaust gas leak detected? 

   YES >>: Repair or replace error-detected parts.

   NO >>: GO TO 2 

1. Listen for an intake air leak after the mass air flow sensor.
2. Check PCV hose connection.

Intake air leak detected? 

YES >>: Repair or replace error-detected parts.

NO >>: GO TO 3 

1. Turn ignition switch OFF.
2. Disconnect corresponding A/F sensor 1 harness connector.
3. Disconnect ECM harness connector.
4. Check the continuity between A/F sensor 1 harness connector and ECM harness connector.

   +		-		Continuity
   A/F sensor 1		ECM
   Connector	Terminal	Connector	Terminal
   F18	1	F51	56	Existed
   	2		60

5. Check the continuity between A/F sensor 1 harness connector and ground, or ECM harness connector and ground.

   +		-	Continuity
   A/F sensor 1
   Connector	Terminal
   F18	1	Ground	Not existed
   	2

   +		-	Continuity
   ECM
   Connector	Terminal
   F51	56	Ground	Not existed
   	60

6. Also check harness for short to power.

Is the inspection result normal? 

YES >>: GO TO 4 

NO >>: Repair or replace error-detected parts.

If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.

1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.

TESTING CONDITION:

Before performing the following procedure, confirm that battery voltage is more than 11 at idle.

>>: GO TO 5 

1. Clear the mixture ratio self-learning value. Refer to DESCRIPTION .
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Turn ignition switch ON.
4. Turn ignition switch OFF and wait at least 10 seconds.
5. Start engine and keep the engine speed between 3, 500 and 4, 000 rpm for 1 minute under no load.
6. Let engine idle for 1 minute.
7. Keep engine speed between 2, 500 and 3, 000 rpm for 20 minutes.
8. Check DTC.

Is DTC detected? 

YES >>: Refer to REMOVAL AND INSTALLATION .

NO >>: GO TO 6 

Check fuel pressure. Refer to Work Procedure WORK FLOW .

Is the inspection result normal? 

YES >>: GO TO  8

NO >>: GO TO 7 

Check fuel hoses and fuel tubes for clogging. Refer to EXPLODED VIEW .

Is the inspection result normal? 

YES >>: Replace "fuel filter and fuel pump assembly". Refer to EXPLODED VIEW .

NO >>: Repair or replace error-detected parts.

With M.U.T.-III SE

1. Install all removed parts.
2. Check "MASS AIR FLOW SENSOR (g/s)" in "DATA MONITOR" mode of "ENGINE" using M.U.T.-III SE.
3. For specification, refer to COMPONENT INSPECTION .

With GST

1. Install all removed parts.
2. Check mass air flow sensor signal in Service $01 with GST.
3. For specification, refer to MASS AIR FLOW SENSOR: SERVICE DATA .

Is the measurement value within the specification? 

YES >>: GO TO 9 

NO >>: Check connectors for rusted terminals or loose connections in the mass air flow sensor circuit or grounds. Refer to DTC DESCRIPTION .

With M.U.T.-III SE

1. Start engine.
2. Perform "POWER BALANCE" in "Actuator Test" (in "Special Function") mode of "ENGINE" using M.U.T.-III SE.
3. Make sure that each circuit produces a momentary engine speed drop.

Without M.U.T.-III SE

1. Let engine idle.
2. Listen to each fuel injector operating sound.

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   Clicking noise should be heard  .

   Is the inspection result normal? 

   YES >>: INSPECTION END

   NO >>: Perform trouble diagnosis for "FUEL INJECTOR", refer to COMPONENT FUNCTION CHECK .