LTD Country Squire V8-351 5.8L VIN G Windsor 2-bbl HP (1985)
Engine Control Module: Technical Service Bulletins
MCU - Quick Test Revision
Article No. 86-25-11
MCU - QUICK TEST - 5.8L POLICE/CANADIAN TRAILER TOW VEHICLES
FORD 1984-87 FORD
LINCOLN-MERCURY 1984-87 MERCURY
The MCU Quick Test has some directions that could cause a wrong diagnosis. Following is a revision to the MCU Emission Diagnosis Shop Manual,
Page 23-18, Test 6 to aid in proper diagnosis. This revision needs to be added to your Manual.
OTHER APPLICABLE ARTICLES: None
WARRANTY STATUS: "INFORMATION ONLY"
Quick Test
6
TEST STEP
RESULT
ACTION TO TAKE
6.0 SPARK KNOCK, ONLY AT WIDE
OPEN THROTTLE, AND/OR POOR
PERFORMANCE/MILEAGE.
PERFORM STEP 6.3 ON VEHICLES
WITH KNOCK SENSOR ONLY
^
Disconnect knock sensor.
Yes
RECONNECT
ignition module, and
^
Verify initial timing per emission decal.
go to Step 6.1
-
Reset to correct timing if necessary.
^
Verify vehicle is at normal operating
No
REPLACE ignition
temperature.
module, and repeat
-
Disconnect the two wire ignition
all of Step 6.0
module connectors (yellow wire,
Circuit 324 and black/white
wire, Circuit 60) from vehicle
harness.
-
Jumper these two wires together at
the ignition module.
-
Read and record ignition timing.
^
Remove jumper wire.
-
Reread ignition timing.
^
Did timing retard 16-20 degrees when jumper was removed?