Cylinder Balance Test

HOW TO INITIATE
The test is entered by depressing and releasing the throttle within two minutes after the Key On Engine Running (KOER) self test codes have been outputted. Refer to Key On Engine Running (KOER) Self Test.


OBTAINING RESULTS
The results of the test are output as a trouble code. These codes are not stored in the continuous memory and must be read and recorded as they occur.

CODE WEAK CYLINDER #
10 1
20 2
30 3
40 4
50 5
60 6
70 7
80 8
90 System Pass
77 Test aborted

The test may be repeated three times. With each test the criteria used to determine a weak cylinder is progressively increased.

Failed first test slightly weak cylinder
Failed second test weak cylinder
Failed third test very weak/dead cylinder

For a more detailed description of the criteria used to determine a weak cylinder refer to Quick Test Description. Quick Test Description


NOTE: Do not move the throttle during this test. Any variation in the throttle position sensor signal to the powertrain control module will cause the test to abort and output a code 77.