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Home >> Ford >> 1990 >> Bronco II RWD, Standard, M5OD-R1 >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Tests W/Codes >> Test H - Fuel Control >> Test H: Step 9
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Test H: Step 9

9) Cylinder Balance Test: Sequential PFI Engines ONLY  Perform KOER Self-Test. After last code is displayed, wait 5-10 seconds. Enter CYLINDER BALANCE TEST by briefly opening throttle for one second (not WOT). Test time is approximately 2-3 minutes. A Code 77 indicates that the throttle was touched when the test was running and that the test was not completed. Use table to interpret codes received from test. If balance test does not display Code 90, go to step 4). If balance test displays Code 90 (Pass), fuel delivery is okay, fault is in an area common to all cylinders (except vehicles with Codes 41/91 or 42/92). Vehicles with Code 41 or 91 displayed, go to next step. If a Code 42 or 92 is displayed, go to step 23).

CYLINDER BALANCE TEST SERVICE CODES

Service Code Cylinder or Injector No. Breakout Box Test Pin No.
90 (Pass) (Pass)
10 1 58
20 2 59
30 3 12
40 4 13
50 5 14
60 6 15
70 7 42
80 8 52
77 (Retest) (Retest)
NOTE: There is a break in the step numbering sequence at this point, skipping from step 9) to step 11). Break is due to previous chart references to these testing procedures. No test procedures have been omitted.