Caterpillar Fault Code
Free · no signupSPN 102 FMI 3
Low power; Excessive black smoke; Poor throttle response; "Lazy" turbo feel.
System
Not specified
Symptom
Low power; Excessive black smoke; Poor throttle response; "Lazy" turbo feel.
Diagnosis & fix steps
Intake Manifold Pressure Voltage High
LOGIC: Boost signal wire open or shorted to 5V.
ACTION: Inspect turbo ducting for leaks. Jumper pins to check for FMI 4. Check for soot in sensor orifice.
FIX: Clean sensor port or replace Intake Pressure (Boost) Sensor.
Red Seal field insights
High-idle machines often "soot up" the sensor. Clean the orifice with a pick before buying a new sensor.
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