Cylinder Balance Test - Actron Code Scanner CP9015 Instruction Manual

This test is only used on vehicles with
Sequential electronic Fuel Injection
(SFI) engines. (Where the injectors are
fired individually in the same sequence
as the spark plug firing sequence.) The
test turns each injector on and off and
checks for an RPM decrease. Codes
indicate cylinders which are weak or not
contributing due to problems such as
damaged injectors, spark plugs and
wiring. The test must be run at the end
of the normal Key On Engine Running
Self-Test procedure (explained in
Section 4) and may be repeated as
often as desired.
Warning: The following procedure
involves starting the engine.
Always operate vehicle in a well
ventilated area.
Exhaust gases are very poisonous!
1) Safety First!
• Set the parking brake.
• Put shift lever in PARK (automatic
transmission) or NEUTRAL (manual
transmission).
• Block the drive wheels.
2) Make Sure Ignition Key is in OFF
Position
3) Check Code Scanner Battery
• Refer to Section 2.
4) Connect Code Scanner
• Refer to Section 3.
• Plug BOTH test connectors into the
Code Scanner!
5) Put Hold/Test Switch in HOLD
Position
6) Have a Pencil and Paper Ready
• This is for writing down the codes.
7) Start the Engine
• Stay away from moving parts.
8) Put Hold/Test Switch in TEST
Position
• Computer is now running normal
Key On Engine Running Self-Test.
9) Wait For End of All Service Code
Signals
• STO light on Code Scanner stops
blinking.
10) Lightly Press and Release Throttle
about 10 seconds after STO Light
stops blinking
• Do NOT press throttle all the way
down!
Exception: Do brief wide-open-
throttle for 1986 only.
• Test time is less than 3 minutes.
• Do not move throttle until test is
over.
11) Get Codes from Flashing STO
Light
• Count flashes to get codes.
NOTE: This test can give single
digit codes.
Code 3 looks like:
FLASH FLASH FLASH
Code 12 looks like:
FLASH (pause) FLASH FLASH
(FLASH=1, FLASH FLASH=2.
Put 1 and 2 together = code 12.)
• Testing is complete
35
PAUSE