Basic Ignition Advance Angle

The ECU calculates the basic advance angle by evaluating engine rpm and intake air volume signals. These sensors' signals have the most significant effect on basic timing calculation.


There are other sensor inputs which also affect the basic spark advance angle. The A/C compressor clutch signal advances basic spark angle when the IDL contacts are on (on some engines), and on the 3S-GTE engine, basic advance angle is retarded if the ECU judges that regular fuel is being used, based on signals from the engine knock (KNK) sensor.

Do It Yourself Car Diagnosis

Do It Yourself Car Diagnosis

Don't pay hundreds of dollars to find out what is wrong with your car. This book is dedicated to helping the do it yourself home and independent technician understand and use OBD-II technology to diagnose and repair their own vehicles.

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