SPN 108 — Barometric Pressure
System: Sensors
Outside air pressure, used to correct fueling and boost for altitude.
Can I keep running it?
LOW — usually OK to keep running
Usually a minor drivability issue, but get it fixed so boost and fueling stay accurate.
Likely causes
- Faulty barometric sensor (often inside the ECM)
- Wiring fault on external sensors
- ECM internal fault
Checks & fixes (easiest first)
- Compare reading to local barometric pressure
- Inspect wiring on external sensors
- Check for ECM supply voltage codes
Common FMIs with SPN 108
- SPN 108 FMI 2Data erratic, intermittent, or incorrect
- SPN 108 FMI 3Voltage above normal or shorted high
- SPN 108 FMI 4Voltage below normal or shorted low
Related codes
- SPN 102Intake Manifold #1 Pressure (Boost)
FAQ
What does SPN 108 mean?
SPN 108 is Barometric Pressure. Outside air pressure, used to correct fueling and boost for altitude.
Can I keep running with SPN 108?
Usually a minor drivability issue, but get it fixed so boost and fueling stay accurate.
What causes SPN 108?
Faulty barometric sensor (often inside the ECM); Wiring fault on external sensors; ECM internal fault.