Ford 2005 Grand Marquis Owner's Manual page 240

Maintenance and Specifications
These temporary malfunctions can be corrected by filling the fuel tank
with good quality fuel and/or properly tightening the fuel cap. After three
driving cycles without these or any other temporary malfunctions
present, the Check engine/Service engine soon light should turn off. (A
driving cycle consists of a cold engine startup followed by mixed
city/highway driving.) No additional vehicle service is required.
If the Check engine/Service engine soon light remains on, have your
vehicle serviced at the first available opportunity.
Readiness for Inspection/Maintenance (I/M) testing
In some localities, it may be a legal requirement to pass an I/M test of
the on-board diagnostics system. If your Check engine/Service engine
soon light is on, refer to the description in the Warning lights and
chimes section of the Instrument Cluster chapter. Your vehicle may not
pass the I/M test with the Check engine/Service engine soon light on.
If the vehicle's powertrain system or its battery has just been serviced,
the on-board diagnostics system is reset to a "not ready for I/M test"
condition. To ready the on-board diagnostics system for I/M testing, a
minimum of 30 minutes of city and highway driving is necessary as
described below:
• First, at least 10 minutes of driving on an expressway or highway.
• Next, at least 20 minutes driving in stop-and-go, city-type traffic with
at least four idle periods.
Allow the vehicle to sit for at least eight hours without starting the
engine. Then, start the engine and complete the above driving cycle. The
engine must warm up to its normal operating temperature. Once started,
do not turn off the engine until the above driving cycle is complete.
POWER STEERING FLUID
Check the power steering fluid.
Refer to the scheduled
maintenance information for the
service interval schedules. If adding
fluid is necessary, use only
MERCON ATF.
1. Start the engine and let it run until it reaches normal operating
temperature (the engine coolant temperature gauge indicator will be
near the center of the normal area between H and C).
240
2005 Crown Victoria (cro)
Owners Guide (post-2002-fmt)
USA (fus)