When the error codes come up, there is no throttle control at all. The engine just and I mean only just ticks over and  sounds like a wet fart on loudspeaker. You can press the throttle all you like and get absolutely no response... When you clear the error codes, the engine runs sweetly and the throttle is absolutely fine. The only obersvation I've notices is that once the car starts hunting for gears, within the next few times I start the car I can almost always guarantee the same error codes will come up and the symptoms described will reappear.