Vehicle applicability: This diagnostic supplement covers multiple Ford vehicles and engines. Follow the application named in the source below. Some references apply to vehicles other than Mustang.
EM7 CHECK FOR EXCESSIVE CARBON MONOXIDE (CO) LEVELS
Does the vehicle have excessive CO levels?
Yes | No |
|---|---|
Excessive CO levels indicate the engine is running rich. GO to EM10 . | GO to EM8 . |
EM8 CHECK FOR EXCESSIVE HYDROCARBON (HC) LEVELS
Does the vehicle have excessive HC levels?
Yes | No |
|---|---|
Excessive HC levels with low to normal CO levels indicate the engine is running lean. GO to EM16 . | GO to EM9 . |
EM9 CHECK FOR EXCESSIVE OXIDES OF NITROGEN (NOX) LEVELS
Does the vehicle have excessive NOx levels?
Yes | No |
|---|---|
GO to EM20 . | VERIFY the test step results. |
EM10 HIGH CO LEVELS: CHECK THE HC LEVELS
Does the vehicle have excessive HC levels?
Yes | No |
|---|---|
CHECK for the engine running rich and incomplete combustion. GO to EM11 . | GO to EM12 . |
EM11 CHECK THE SECONDARY IGNITION SYSTEM
• For ignition coil on plug (COP) equipped vehicles, GO to JB3 and follow the pinpoint test direction.
• For ignition coil pack equipped vehicles, GO to JC3 and follow the pinpoint test direction.
Is a concern present?
Yes | No |
|---|
2016 Mustang workshop publication supplied to Mustang Atlas. Original technical text and illustrations; HTML formatting by Mustang Atlas. Source page numbering is retained for traceability. Follow the configuration, revision, warnings, and cross-references in the material. About this edition.