My Renault Senic Megane has an intermittent problem it clunks then loses power a message comes up saying electronic fault check gearbox. If the car is turned off and then back on the fault disappears.
It doesn't lose power but as it puts you in third gear it struggles to pull away. The transmission computer has detected a fault. Codes need to be read and a look at live data, especially pressures. Commonest fault is pressure regulation.
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