2074072

Check Air Leakage

(1)

Visually/physically inspect the air leakage in intake/exhaust system as following items.

(1) If OK, go to "Check for air leakage in EVAP.Purge control valve" as below

(2) 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

(2)

Check for air leakage in EVAP. Purge control valve.

(1) With engine idling disconnect hose from EVAP purge valve side of hose

(3) Is vacuum available at purge valve when EVAP. purge valve is not in operating ?

YES

Repair or replace as necessary and go to "Verification of Vehicle Repair" procedure.

Go to "Check for air leakage in Positive Crankcase Ventilation Valve(PCV)" as below.

(3)

Check for air leakage in Positive Crankcase Ventilation Valve(PCV).

(1) Remove PCV valve from cylinder head cover by pulling ventilation hose

(2) With engine idling block PCV valve opening

(3) Comfirm that vacuum is felt

(4) Revmove PCV valve

(5) Blow through valve from prot "A" and verify that air comes out of prot "B"

(6) Blow through valve from prot "B" and verifty that no air comes out of port "A"

(7) Have a problem been found ?

YES

Repair or replace as necessary and go to "Verification of Vehicle Repair" procedure.

Go to "Fuel Presure Test" as below.

Fuel Pressure Test

note

1.Be cautious that Fuel is explosive and an empty fuel tank can still contain explosive gases.When working on fuel system make sure to supply adequate ventilation to the work area. Do not smoke, and keep sparks and open flames away.

2.The fuel system remains under pressure when the engine is not running. Release fuel system pressure before disconnecting any fuel line to reduce the chance of presonal injury or fire damage to vehicle components.

(1)

Check the fuel for excessive water, alcohol, or other contaminants. Replace contaminated fuel as necessary.

(2)

Install the fuel pressure gauge to the fuel pressure gauge adaptor.

(3)

Apply battery voltage to the terminal for the pump drive and activate the fuel pump: then, with fuel pressure applied, check that there is no fuel leakage from the pressure gauge or connection part.

(4)

Disconnect the vacuum hose from the pressure regulator, and plug the hose end. Measure the fuel pressure at idle.

Specification : 320~340kPa(3.26~3.47 kg/㎠, 46~49 psi)

(5)

Measure the fuel presure when the vacuum hose is connectoed to the pressure regulator.

Specification : Approx. 255kPa(2.57 kg/㎠, 37 psi)

(6)

Are the measured fuel pressure within specifications ?

YES

Go to "Check injector leakage" as below

Repair or replace according to the below table. And then, go to " Verification of Vehicle Repair"procedure.

Condition	Possible Cause
Fuel Pressure is too low	Fuel filter,fuel pressure regulator, in-tank fuel hose or the fuel pump
Fuel Pressure is too high	Fuel pressure regulator, hose or pipe
No different fuel pressure when vacuum hose is connected or not	The vacuum hose or the nipple

Check Injector clog

(1)

Ignition " OFF " after checking the Fuel Pressure Test.

(2)

Stop the engine and check for a change in the fuel pressure gauge reading for 5 minutes.

(3)

Does fuel pressure drop after engine is stopped ?

YES

Substitute with a known - good PCM and check for proper operation.

If the problem is corrected, replace PCM and go to "Verification of Vehicle Repair" procedure.

Repair or replace according to the below table. And then, go to " Verification of Vehicle Repair"procedure.

Condition	Possible Cause
Fuel Pressure reading drops slowly after engine is stopped	Injector leakage
Fuel Pressure reading drops immediately after engine is stopped	Fuel pump