When you lift up the bonnet there's a massisve plastic cover over the engine which has the oil cap in it, but it means i cant see anything. can this be removed? as i think it rattles against something louder than the diesel engine!

Yep, just pull it off. It is a tight fit, so careful youcdon't snap it.

take the oil filler cap off and remove the dipstick then there are two rubber poppers at the front, one at the back......just give it a sharp tug and it will come off

Thanks for the advice. It might just have been pushed down on too much.

Yip just pulls off, and fitting is the reverse of removal :-)

On a similar thing...if you need to take the covers off the battery, be more careful as these don't just pull off - you have to press the right bits before it unflaps. Easy broken if you tug and push the wrong way :(