Equus 3120 - OBD 2&1 Tool Kit - Manual (Page 60)

58 OBD2 & 1
E
Ford OBD1 Systems
ADDITIONAL TESTS FOR EEC-IV SYSTEMS - CYLINDER BALANCE TEST
6. When instructed by the message on the
Tool's display, start the engine and press
the ENTER button. A "One moment
please preparation for test is in
progress..." message shows temporarily
on the Tool's LCD display.
7. When prompted by the message on the
Tool's display, lightly press the accelera-
tor pedal half way and release to acti-
vate the cylinder balance test.
For 1986 models ONLY: Fully
press accelerator once and
release.
■ The computer is now in Cylinder
Balance Test mode, and will start cut-
ting fuel to each cylinder in sequence to determine if all the cylin-
ders are contributing equally. It may take up to five minutes
before the test results are transmitted to the Tool.
8. If the vehicle's computer fails to enter Cylinder Balance Test mode,
do the following:
■ Lightly press the accelerator pedal again as described in step 7
above.
■ Check your vehicle's fuel injection system and make sure that it
is a Sequential Electronic Fuel Injection (SEFI) system. This test
is applicable only to SEFI or SFI systems.
9. After the Cylinder Balance Test is com-
pleted, the test results are sent to the
Tool.
■ The computer compares the power
contribution that each cylinder makes
to engine operation.
10. If all cylinders are contributing equally,
the computer determines that power dis-
tribution is normal and a “System Pass”
message will display.
If the computer detects a prob-
lem with a cylinder(s) when
performing the initial Cylinder
Balance Test, it needs to repeat
the test two more times to properly determine which
cylinder or cylinders are malfunctioning. If this is the
case, the Tool will display the “Lightly press the acceler-
ator half way and release” message again instead of the
“System Pass”. Proceed to step 11.