I've started having this problem where intermittently the car won't accelerate at full power. The instant mpg is as if it is at full throttle but its no where near, its almost as if the brakes are on. It usually only does it once the car is warm and does it particularly at low speeds. There aren't any warning lights or anything. Please help

 

These have variable vane turbos, maybe they are stuck?

 

Get the fault codes read!

 

There aren't any fault codes

 

I should have mentioned that it is the petrol 2.0. It doesn't have a turbo

 

What did you read them on, not all readers display all the codes. It sounds like a faulty sensor of some description, so I'm surprised there are no codes?