Engine oil leak - Valve cover gasket

[wheelywonderful]

Folks

Ive got a puzzler. Any help appreciated.

I have an engine oil leak. It is coming from the valve cover gasket at the rear of the engine where there is a D shaped cutout. Have replaced the gasket, used gasket cement. But no improvement.

There is a fair amount of oil dripping onto the plastic undertray having run to the front and rear of a heat guard.

Whats my next move?
Thanks

[cazyp]

Is it coming from the cam cover?
What car/engine have you got?

[snapdragon]

Is the D-shaped part of the gasket getting dislodged when fitted together Sometimes you need to glue a handle onto it made of dowel etc.. so you can pull it outwards.

[wheelywonderful]

Thanks for your initial thoughts.
My engine is a 1.8 20v Turbo with 130k on the clock.

The oil leak appears to be weeping from the D cutout at the rear of the valve cover. I park on a hill so if nose down the oil runs to the front of the car along a heat shield and then down or if I park uphill it drops straight down.

There is a fair amount of oil present so there could even be another leak.

[martin1810]

Take thr filler cap off when it's running, see how much pressure you have. Could be a breather pipe blocked which will lead to seals failing and oil loss..