3.
Was a problem found in any of the above areas?
 | ▶ Repair or replace as necessary. Go to "Verification of Vehicle Repair" procedure. |
 | ▶ Go to next step as below. |
Visually/physically inspect the air leakage in intake/exhaust system for the following areas:
▶ Air cleaner filter element for excessive dirt or for any foreign objects
▶ Throttle body inlet for damage or for any foreign objects
▶ Throttle bore and throttle plate for chocking and for any foreign objects
▶ Restricted exhaust system
▶ Exhaust system between HO2S and three way catalyst for air leakage
Inspect the leakage in EVAP. system for the following conditions:
▶ Check the EVAP canister for fuel saturation. If the EVAP canister is full of fuel, visually and physically inspect the EVAP and fuel system.
Was a problem found in any of the above areas?
| ▶ Repair or replace as necessary. Go to "Verification of Vehicle Repair" procedure. |
| ▶ Go to next step as below. |
Visually/physically inspect the front HO2S for the following conditions:
▶ Ensure that the HO2S is securely installed.
▶ Silicon contamination. This contamination will be indicated by a white powdery coating on the portion of the sensor exposed to the exhaust stream and this will result in a but false(high) voltage signal
▶ Fuel, engine coolant or oil contamination
▶ Use of improper sealant
Visually/physically inspect the MAFS for the following conditions:
▶ Contamination or deterioration
▶ Poor connection or damaged harness
Check for an intermittent TPS1 false signal. TPS1 signal displayed on a scantool should increase steadily when depressing accelerator pedal after starting.
Verify that the PCM/ECM ground connections are clean and properly tightened.
If test result is NG, repair or replace as necessary and go to "Verification of Vehicle Repair" procedure.
If OK, go to next step as below.
If the contamination is evident on the HO2S or MAFS. Fix the source of the sensor contamination before replacing the sensor to prevent future contamination.
Check the engine oil level. The oil level should be between the min. and max. marking. Fill to the correct oil level.
Check crankcase ventilation valve for improper installation, damaged o-rings and malfunctioning.
Repair or replace as necessary and go to "Verification of Vehicle Repair" procedure. If OK, go to next step.
Check the fuel for excessive water, alcohol, or other contaminants. Replace contaminated fuel as necessary.
Install a fuel pressure gage.
Inspect fuel pressure with normal idle status.
Specification : 323 ~ 363 kPa (3.29 ~ 3.55 kgf/㎠, 46.8 ~ 52.6 psi)
Is fuel pressure within the specified value?
| ▶ Go to next step as below. |
| ▶ Inspect the suspected area. Refer to table as below. Repair or replace as necessary and go to "Verification of Vehicle Repair" procedure. |
Condition | Possible Cause | Suspected Area |
Fuel Pressure is too low | Clogged fuel filter | Fuel filter |
Fuel leak on the fuel-pressure regulator that is assembled on fuel pump | Fuel Pump(Fuel Pressure Regulator) | |
Fuel Pressure is too high | Sticking fuel pressure regulator | Fuel Pump(Fuel Pressure Regulator) |
Stop the engine and check for a change in the fuel pressure gauge reading.
Specification : After engine stops, the gauge reading should hold for minimum 5 minutes
Is fuel pressure within the specified value?
| ▶ Go to next step as below |
| ▶ Inspect the suspected area. Refer to table as below. Repair or replace as necessary and go to "Verification of Vehicle Repair" procedure. |
Condition | Possible Cause | Suspected Area |
Fuel pressure drops slowly | Injector leak | Injector |
Fuel pressure drops immediately | Stuck open check valve of the fuel pump | Fuel pump |
