Detailed guide for SPN 98 FMI 1
Back to top ↑What SPN 98 FMI 1 means
SPN 98 identifies engine oil level. FMI 1 indicates that the engine oil level is below the normal operating range at the most severe level.
A genuinely low oil level can eventually cause low oil pressure and serious engine damage.
What you may notice
A low-oil-level warning or fault lamp may appear. Some engine applications can derate or use another engine-protection response when the condition is severe.
What to check first
Park the vehicle on level ground and verify the oil level using the manufacturer's procedure.
If the level is low, inspect for external oil leaks and determine whether abnormal oil consumption is occurring.
Correct the oil level with the specified oil, but do not stop diagnosis there if the oil level continues dropping.
If the physical oil level is correct but SPN 98 FMI 1 remains active, inspect the oil level sensor, connector and electrical circuit.
Important
Do not confuse SPN 98 with SPN 100. SPN 98 concerns engine oil **level**, while SPN 100 concerns engine oil **pressure**.
Always use the OEM specifications and diagnostic procedure for the specific engine.
Mechanic community notes for SPN 98 FMI 1
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