System Inspection

Check spark plug
1. Remove cylinder's spark plugs
2. Visually/physically inspect the following items:
  - Damaged insulation, worn electrodes, oil or fuel fouled, loose terminals and cracks.
  - Check for plug gap: 1.0 - 1.1 mm (0.039 - 0.043 in.)
  - Check if the spark plug for the relevant cylinder is lighter in color than the other plugs.
3. Has a problem been found in any of the areas above?
  YES
  - Repair or replace as necessary. Go to "VERIFICATION OF VEHICLE REPAIR " procedure
  NO
  - Go to "CHECK AIR LEAKAGE" as follows. (Refer to 2)
Check air leakage
1. Visually/physically inspect for air leakage in the intake/exhaust system focusing on the following items:
  - 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 exhaust manifold and three-way catalyst for air leakage.
2. Has a problem been found in any of the areas above?
  YES
  - Repair or replace as necessary. Go to "VERIFICATION OF VEHICLE REPAIR " procedure
  NO
  - Go to "CHECK FOR AIR LEAKAGE IN POSITIVE CRANKCASE VENTILATION (PCV) VALVE". (Refer to 3)
Check for air leakage in Positive Crankcase Ventilation (PCV) valve
1. Remove PCV valve from cylinder head cover by pulling ventilation hose.
2. With engine idling block PCV valve opening.
3. Verify that vacuum is felt.
4. Remove PCV valve.
5. Blow through valve from port "A" and verify that air comes out of port "B".
6. Blow through valve from port "B" and verify that no air comes out of port "A".
7. Has a problem been found in any of the areas above?
  YES
  - Repair or replace as necessary. Go to "VERIFICATION OF VEHICLE REPAIR " procedure
  NO
  - Go to "CHECK COMPRESSION PRESSURE" as follows. (Refer to 4)
Check compression pressure
1. Warm up the engine to normal operating temperature.
2. Disconnect the spark plug cables and remove the spark plugs.
3. Crank the engine to remove any foreign material in the cylinders.
4. Put compression pressure gauge into spark plug hole.
5. Crank the engine with throttle valve wide open and check compression pressure at each cylinder.
  Specification: 1, 029kPa (10.5kgf/cm² , 149psi) (250~400 rpm)
6. Is compression pressure for each cylinder displayed within specifications?
  YES
  - Go to "CHECK TIMING" as follows. (Refer to 5)
  NO
  - Add a small amount of oil through the spark plug hole, and repeat the steps above. If the addition of oil causes the compression to rise, the cause is a worn or damaged piston ring or cylinder inner surface.
  - If the compression remains the same, the cause is a burnt or defective valve seat, or pressure is leaking from the head gasket. Repair as necessary. Go to "VERIFICATION OF VEHICLE REPAIR " procedure
Check timing
1. IG "OFF"
2. Monitor the signal waveforms for Camshaft and Crankshaft position Sensor are correctly aligned.
  Reference: The 17th CKP signal after the missing tooth is aligned with the high voltage CMP signal.
  
  Fig 1: Scantool Display - CKPS And CMPS Voltage Signal Waveforms
  Courtesy of KIA MOTORS AMERICA, INC.
  
  Fig 2: Identifying Alignment Marks On Timing Chain
  Courtesy of KIA MOTORS AMERICA, INC.
3. Are all timing marks aligned correctly?
  YES
  - Go to "CHECK FUEL PRESSURE" procedure. Refer to 6)
  NO
  - Check that Cam, Crank and Oil pump sprocket timing marks are correctly aligned. Repair or readjust as necessary. Go to "VERIFICATION OF VEHICLE REPAIR " procedure

Check fuel pressure

NOTE:

Gasoline or gasoline vapors are highly flammable/explosive and an empty fuel tank can still contain explosive vapors. A fire could occur if an ignition source is present. When working on fuel system make sure that the work area has adequate ventilation. Do not smoke. Keep sparks and open flames away at all times.
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 personal injury or fire damage to vehicle components.

IG "OFF". Disconnect fuel pump relay in junction box.
Start the engine and wait until it stalls.
IG "OFF". Connect fuel pump relay.
Install the low fuel pressure gauge to the delivery pipe using the fuel pressure gauge adaptor. (refer to the appropriate service information)
Activate the low fuel pump, and check that there are no fuel leaks from the pressure gauge or fuel system.
Measure the fuel pressure at idle.
Specification: 400 ~ 600 kPa (4.07 ~ 6.12 kg/cm² , 58 ~ 87 psi)

Is the measured fuel pressure within specifications?

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 chart below. 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 in-tank fuel pump
Fuel pressure is too high	Fuel pressure regulator, hose or pipe