Detailed guide for SPN 91 FMI 8
Back to top ↑When the pedal signal jumps, the ECM plays it safe and cuts response. Most fixes are under the dash, not under the hood.
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Share ↓SPN 91 FMI 8Severity: Warning
SPN 91 FMI 8: Accelerator pedal signal abnormal – hesitation or limp response
Quick Answer
Accelerator pedal signal abnormal – hesitation or limp response
Code
SPN 91 FMI 8
Severity
Warning
Applies to
Check OEM application
Can I drive?
Driving suitability is not established by this code alone.
Common Symptoms
- Delayed throttle response
- Feels like “dead pedal” at times
- Intermittent limp mode
Likely Causes
- Pedal sensor wear
- Loose/corroded connector under dash
- Wiring damage
Common Fixes
- Inspect connector and pin fit
- Check signal sweep with scan tool
- Replace pedal assembly if signal is unstable
Full technical sections↓
What does SPN 91 FMI 8 mean?
Back to top ↑Accelerator pedal signal abnormal – hesitation or limp response
Video walkthrough for SPN 91 FMI 8
The videos below are embedded using YouTube’s official player. We do not host or claim ownership of this content. Use it as a visual reference and always confirm with diagnostics for your exact truck configuration.
SPN 91 FMI 8 | How To Replace The Accelerator Pedal On A Freightliner Cascadia | PT. 1
Channel: The Golden Trucker • View in BigRigFaults Media • YouTube source
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