You may have a slipping torque converter clutch or worn bands. Contact a local transmission repair shop for further diagnoisis. The turbine speed sensors measure in and out speed of the main shaft, if a excess differance is seen then it will turn on the light and set the appropriate fault codes.
SOURCE: Service engine light
Your not going to here any knock from the engine the knock sensor detects detonation which is not detectable with the human ear. if you want to test the knock sensor you can tap the side of the block the engine should stumble for a couple of seconds if it does not change then the way the engine runs then the knock sensor is defective or hase buildup iside the engine and you will need to do a top engine clean. if you want instructions on how to do this just post another post to this reply This happens on engines that ave high mileage or acar that runs low grade like regular.
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http://engine-codes.com/p0715_mitsubishi.htmlForum CodePossible causes - Transmission speed sensor circuit is open or shorted
Help with thisWhen is the code detected?Diagnostic Trouble Code (DTC) P0715 is detected when TCM or ECM does not receive the proper signal from the sensor.Symptoms- Engine Light ON (or Service Engine Soon Warning Light)http://engine-codes.com/p0715_mazda.htmlForum CodePossible causes- Transmission speed sensor circuit is open or shorted. 556 views
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codes sets at idle, not moving....and if this matters at all engine rpm is lower than turbine shaft measured rpm....I would think that if its slipping it would be the opposite.
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