P0178 Diagnostic Trouble Code Discussion for July 2026
Fuel Composition Sensor Low Frequency
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| Help Request | Posted | |
| 2003 Chevrolet Tahoe LT 5.3L MIL Lamp on VIN: 1GNEK13Z93 P0178: Fuel Composition Sensor Low Frequency. Truck has Code P0178 fuel composition sensor out of range. Scanner shows it at 43hertz and 38 % alcohol which seems to be a default number. Has 12 volt power and ground at sensor(load tested with a 1156 bulb). Pin dragged all pins at sensor and PCM, all go... |
July 02, 2026 |
