If everything in the system is functioning smoothly, both LTFT and STFT values should be close to 0.

Question

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LTFT (Long Term Fuel Trim) and STFT (Short Term Fuel Trim) values are adjustments made by the engine control unit (ECU) to the fuel mixture. When everything in the system is functioning smoothly, these values should be close to 0%, indicating that the engine is running efficiently with minimal need for fuel mixture adjustments.

If Everything in the System Is Functioning Smoothly, Both LTFT