Further to the two other know causes of intermittent power loss on I-CTDI as discussed here. ERG Valve Stuck Fuel Diagnostic On completion of the above two steps you still find you are no way closer to resolving the power loss issue, carry out the following inspection. This fault can also be caused by a low coolant level, coolant leak or air in the cooling system causing excessive coolant temperatures. The ECU software has a built in safety feature whereby it will start to limit engine power if the coolant temperature exceeds approximately 118 degrees C, but if the coolant temperature continues to rise then the engine power will continue to be limited until eventually the engine will cut out to protect itself from damage. TIP Applicable to stock car , remaps cars consult your remapping firm for a solution.