Ford Historic (OBD I) Diagnostics
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6
Cylinder (Cyl) Balance Test (EEC-IV Vehicles)
✓The Cyl Balance Test is only applicable to engines equipped with
EEC-IV Sequential Electronic Fuel Injection (SEFI or SFI).
✓The Cyl Balance Test identifies a weak cylinder(s) on EEC-IV
vehicles. A weak cylinder may be caused by low compression,
poor valve seating, fouled spark plugs, damaged fuel injectors,
and other cylinder faults. The PCM shuts off the fuel supply to each
cylinder and measures the RPM drop. The PCM then calculates
variations between cylinders thus identifying the weak ones.
Exhaust gases are harmful or lethal. Always
operate vehicle in a well-ventilated area.
The Cyl Balance Test is done with the engine
running. Do not over-rev engine. Observe all safety
precautions.
From the On Demand Test Menu:
1. Select Cyl Balance Test.
•Use the
UP
or
DOWN
arrow
keys until Cyl Balance Test is
highlighted.
•Press
ENTER.
Keep hands and tools away from fan and engine
during test.
2. Perform the following:
1) Set parking brake.
2) Transmission in park (P) or neutral (N).
3) Turn A/C off.
4) Start engine and let idle until hot.
5) Turn ignition key off.
6) Wait 10 seconds. Start engine and let idle.
7) If vehicle is equipped with a manual transmission, release clutch.
Press
ENTER to continue.
!
WARNING
!
CAUTION
Wiggle Test
Output Sw Test
Cyl Balance Test
STAR Test Mode
Review Data
Print Data
Tool Setup
On Demand Test Menu
Cyl Balance Test
!
CAUTION