F 150 4WD V8-5.4L Flex Fuel (2008)
Spark Plug: Customer Interest
Ignition/Fuel Systems - Misfire on Steady Cruise
TSB 07-24-8
12/10/07
ENGINE MISFIRE DURING CRUISE WITH OR
WITHOUT DTCS (MEXICO ONLY)
FORD:
2007-2008 Expedition, F-150, F-250
LINCOLN:
2007-2008 Mark LI, Navigator
ISSUE
Some 2007-2008 Expedition, Navigator, Mark LT, F-150 and F-250 vehicles equipped with a 5.4 3V engines may exhibit engine misfire during cruise,
rough run, hesitation, buck jerk, with or without diagnostic trouble codes (DTCs).
ACTION
Follow the Service Procedure steps to correct the condition.
SERVICE PROCEDURE
1.
Use Motorcraft(R) Carburetor Tune-Up Cleaner to clean engine combustion system.
a.
Disconnect canister purge line from the intake manifold.
b.
Attach a vacuum line to the purge port.
c.
At hot engine idle, allow the engine to ingest about a 1/2 to 2/3 of a can of Motorcraft(R) Carburetor Tune-Up Cleaner. Use caution not to
ingest too quickly due to potential hydro-lock issues. Read the entire label on the Motorcraft(R) Carburetor Tune-Up Cleaner. Shake the can
well before using and make sure to use at room temperature.
d.
Shut the engine off and allow it to soak for one hour.
e.
Start engine, allow the engine to ingest the remainder of the Motorcraft(R) Carburetor Tune-Up Cleaner.
f.
Reconnect canister purge vacuum line.
g.
Cycle engine between idle and 2500 RPM for about 5 minutes.
2.
Inspect the spark plugs for abnormal fouling.
3.
Replace fouled spark plugs.
4.
Re-gap the spark plug to .035" (0.9 mm).
Parts Block
WARRANTY STATUS: Eligible Under Provisions Of New Vehicle Limited Warranty Coverage And Emissions Warranty Coverage
IMPORTANT: Warranty coverage limits/policies are not altered by a TSB. Warranty coverage limits are determined by the identified causal part.
OPERATION
DESCRIPTION
TIME
072408A
2007-2008
1.9 Hrs.
Expedition/Navigator/F-150/F-250/Mark
LT 5.4L 3V: Check DTCs,
