gas mileage Mercury Grand Marquis 1998 Owner's Manuals

Fuel quality
If you are experiencing starting, rough idle or hesitation driveability
problems during a cold start, try a different brand of ªRegularº unleaded
gasoline. ªPremiumº unleaded gasoline is not recommended (particularly
in the United States) because it may cause these problems to become
more pronounced. If the problems persist, see your dealer or a qualified
service technician.
The American Automobile Manufacturers Association (AAMA) issued a
fuel specification to provide information on high quality fuels that
optimize the performance of your vehicle. We recommend the use of
fuels that meet the AAMA specification if they are available.
It should not be necessary to add any aftermarket products to your fuel
tank if you continue to use a high-quality fuel.
Cleaner air
Ford approves the use of gasolines to improve air quality, including
reformulated gasolines that contain oxygenates up to 10% ethanol or
15% MTBE.
Do not use gasolines containing methanol, which can damage critical fuel
system components. Damage resulting from the use of methanol may not
be covered by your warranty.
Running out of fuel
Avoid running out fuel because this situation may have an adverse affect
on powertrain components.
If you have run out of fuel: You may need to crank the engine several
times before the system starts to pump fuel from the tank to the engine.
If you run out of fuel, your Check Engine light may come on. For more
information on the Check Engine light, refer to theInstrumentation
chapter.
Calculating fuel economy
To accurately calculate your vehicle's fuel economy:
1. Fill the tank completely and record the initial odometer reading.
2. Each time you fill the tank, record the amount of fuel added (in liters
or gallons).
3. After at least three to five fuel tank fill-ups, fill the fuel tank and
record the current mileage reading.
Maintenance and care
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