Engine Compression Test

■Measure the engine compression

1. Warm up and stop engine.
2. Remove the engine cover.
3. Disconnect the GDI/MPI injector connectors.
4. Remove the ignition coil.
5. Remove the spark plugs. (using a 16mm plug wrench, remove the spark plugs)
6. Check the cylinder compression pressure.
   1. Insert a compression gauge into the spark plug hole.
   2. Set the throttle plate in the wide-open position.
   3. While cranking the engine, measure the compression pressure. (always use a fully charged battery to obtain engine speed of 200 rpm or more)
   4. Repeat step 1) through 3) for each cylinder. (this measurement must be done in as short time as possible.)

      Courtesy of KIA MOTORS AMERICA, INC.

      Specification: 

      Standard: 1225.83 kPa (12.5 kg/cm^2, 177.79 psi) (200 to 250 rpm)

      Maximum: 1078.73 kPa (11.0 kg/cm^2, 156.46 psi)

      Difference between each cylinder: 98 kPa (1.0 kg/cm^2, 14 psi) or less

7. Is the measured value within specifications?

   Good 

   • Fault might be intermittent and caused either by poor contact in connectors or wiring harness, or it has been repaired and control module memory is not cleared yet. Thoroughly check terminal of battery, all connectors (and connections) for looseness, bending, corrosion, contamination, deterioration, and/or damage.
   • Repair or replace as necessary and go to "Verification Of Repair " procedure.

   No Good 

   • Go to "Verification Of Repair " procedure.