Visually/physically inspect the air leakage in intake/exhaust system as following items,
If OK, go to next step
If NG, repair as necessary and go to "Verification of Vehicle Repair" procedure
- Vacuum hoses for splits, kinks and improper connections.
- Throttle body gasket
- Gasket between intake manifold and cylinder head
- Seals between intake manifold and fuel injectors
- Exhaust system between HO2S and Three way catalyst for air leakage
Check for air leakage in EVAP. Purge control valve
Remove the manifold side vacuum hose from the EVAP canister purge valve.
Using a hand vacuum pump apply specified vacuum(Approx. 15 in, Hg) to the manifold side of the valve
Does the valve hold vacuum?
YES
Go to "Fuel System Inspection" procedure
NO
Repair air leakage and go to "Verification of Vehicle Repair" procedure
Check the fuel for excessive water, alcohol, or other contaminants. Replace contaminated fuel as necessary.
Disconnect the vacuum hose from the fuel pressure regulator and inspect the hose for the presence of fuel. If any fuel is present in the vacuum hose, replace the fuel pressure regulator. Go to next step
Install a fuel pressure gauge
Start engine and let it idle. With the vacuum hose from the fuel pressure regulator disconnected, inspect fuel pressure
Specification : 320~340kPa(3.26~3.47 kg/㎠, 46~49 psi)
Is fuel pressure within the specified value?
YES
Go to "Fuel Injector Inspection" procedure as below
NO
Repair as necessary refer to inspection note as below and go to "Verification of Vehicle Repair" procedure
Check if fuel line pressure decreases when accelerating quickly
If it does, check fuel pump maximum pressure. If pressure is OK, check fuel line and filter for clogging
If fuel pressure is lower than specification : Check for fuel line pressure while pinching fuel return hose.
If pressure quickly increases, check pressure regulator
If pressure gradually increases, check for clogging between fuel pump and pressure regulator. If hose is not clogged, check fuel pump maximum pressure.
If fuel pressure is higher than specification : Is fuel line clogged?
If it is not, replace pressure regulator.
If it is, replace it
Check the suspect cylinder’s fuel injector for clogging or any restrictions
Test Condition : Ignition "OFF" & Engine "OFF"
Specification : No clogging and restriction
Is the fuel injector OK?
YES
Visually/physically inspect the engine mechanical problem. Repair as necessary and go to "Verification of Vehicle Repair" procedure
NO
Thoroughly check connectors for loose or poor connections, bending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and go to "Verification of Vehicle Repair" procedure
