From the service manual here is a list of things which prevent the Auto Idle Stop from functioning in a M/T model.
- When the transmission is in 1st gear or reverse gear.<<
- When the climate control unit prohibits the engine from stopping.<<
- When the engine coolant temperature is low.<<
- For about 2 minutes after starting the engine.<<
- When the battery state of charge is low.<<
- When the battery module temperature is low.<<
- When the electric load on the 12 V system is high.<<
- When the accelerator pedel is pressed.<<
- When the brake vacuum is low.<<
- When a fault is detected in a related sytem.<<
The engine should stop under the following conditions if all of the above are satisfied.
- When the clutch pedel is pressed with the vehicle speed at 19 mph or less, and the engine speed is at 1,000 rpm or less during deceleration while pressing the brake pedal.<<
- When the clutch pedal is pressed with the vehicle at a stop and in neutral, or when the shift position switch is in neutral with the clutch pedal pressed.<<
If it is not functioning properly you could have a vacuum leak or a faulty sensor.
Hope this helps.
