ZD30 Oil Leak on drivers side of the engine???

[Cowboy]

I have rechecked mine and found the no.1 sleeve is now leaking. I'd agree with doing all at once. Unfortunately I'll have to pull the manifold off this time.

Yep, you are just waisting your time if you don'replace all 4 at the same time, as once the pressure starts to build up it will cause the older ones to leak and when they do, it is generally worse.
We will find out how all ends up today when finished as we had to wait for bloody Nissan to get the gaskets that were needed in, as the local branch didn't have any.... Typical

[BearGUST]

I've returned from a relaxing overseas trip and finally got around to replacing the other 3 injector seals.
It is possible to do them without the removal of the intake manifold. Just remove all the injector lines as a bundle, replace all seals and put it all back together.