Do not make any unauthorized changes to your vehicle or engine. By
law, vehicle owners and anyone who manufactures, repairs, services,
sells, leases, trades vehicles, or supervises a fleet of vehicles are not
permitted to intentionally remove an emission control device or prevent
it from working. Information about your vehicle’s emission system is on
the Vehicle Emission Control Information Decal located on or near the
engine. This decal also lists engine displacement.
Please consult yourWarranty Guidefor complete emission warranty
information.
On-board diagnostics (OBD-II)
Your vehicle is equipped with a computer that monitors the engine’s
emission control system. This system is commonly known as the
on-board diagnostics system (OBD-II). The OBD-II system protects the
environment by ensuring that your vehicle continues to meet
government emission standards. The OBD-II system also assists your
authorized dealer in properly servicing your vehicle. When the service
engine soon
indicator illuminates, the OBD-II system has detected
a malfunction. Temporary malfunctions may cause the service engine
soon
indicator to illuminate. Examples are:
1. The vehicle has run out of fuel—the engine may misfire or run poorly.
2. Poor fuel quality or water in the fuel—the engine may misfire or run
poorly.
3. The fuel fill inlet may not have been properly closed. SeeEasy Fuel™
“no cap” fuel systemin this chapter.
4. Driving through deep water—the electrical system may be wet.
These temporary malfunctions can be corrected by filling the fuel tank
with good quality fuel, properly closing the fuel fill inlet or letting the
electrical system dry out. After three driving cycles without these or any
other temporary malfunctions present, the service engine soon
indicator should stay off the next time the engine is started. A driving
cycle consists of a cold engine startup followed by mixed city/highway
driving. No additional vehicle service is required.
If the service engine soon
indicator remains on, have your vehicle
serviced at the first available opportunity. Although some malfunctions
detected by the OBD-II may not have symptoms that are apparent,
continued driving with the service engine soon
indicator on can
result in increased emissions, lower fuel economy, reduced engine and
transmission smoothness, and lead to more costly repairs.
Maintenance and Specifications
300
2011 05+ Mustang(197)
Owners Guide, 1st Printing
USA(fus)
Readiness for Inspection/Maintenance (I/M) testing
Some state/provincial and local governments may have
Inspection/Maintenance (I/M) programs to inspect the emission control
equipment on your vehicle. Failure to pass this inspection could prevent
you from getting a vehicle registration. Your vehicle may not pass the I/M
test if the service engine soon
indicator is on or not working
properly (bulb is burned out), or if the OBD-II system has determined
that some of the emission control systems have not been properly
checked. In this case, the vehicle is considered not ready for I/M testing.
If the service engine soon
indicator is on or the bulb does not
work, the vehicle may need to be serviced. Refer toOn-board
diagnostics (OBD-II)in this chapter.
If the vehicle’s engine or transmission has just been serviced, or the
battery has recently run down or been replaced, the OBD-II system may
indicate that the vehicle is not ready for I/M testing. To determine if the
vehicle is ready for I/M testing, turn the ignition key to the on position
for 15 seconds without cranking the engine. If the service engine
soon
indicator blinks eight times, it means that the vehicle is not
ready for I/M testing; if the service engine soon
indicator stays on
solid, it means that the vehicle is ready for I/M testing.
The OBD-II system is designed to check the emission control system
during normal driving. A complete check may take several days. If the
vehicle is not ready for I/M testing, the following driving cycle consisting
of mixed city and highway driving may be performed:
15 minutes of steady driving on an expressway/highway followed by
20 minutes of stop-and-go driving with at least four 30-second 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. If
the vehicle is still not ready for I/M testing, the above driving cycle will
have to be repeated.
Maintenance and Specifications
301
2011 05+ Mustang(197)
Owners Guide, 1st Printing
USA(fus)
