Got a lot more done today.
Everything is off the head, ready for removing it. The only stumbling block is the lack of the E12 socket. I did have a set, but I can't find it.
So I've ordered one, but that won't be here for a couple of days.
Hopefully I'll get the head off by the middle of next week.
Then I'll be able to see what's up with it. From a casual glance at the top of the head, with the cam top cover removed, I can't see anything amiss.
I've arrowed the valve that is leaking under compression.
However it does look like someone has been there before, as the head looks like it's been reconditioned.
It also has 4 replacement or refurbished injectors fitted, as all are spotlessly clean.
I wrote the cylinder number I removed each injector from on the body, then discovered that, all the injectors have had the numbers 1,2,3,4 stamped in the top, just under the fuel connection. However the injectors were fitted in the wrong sequence, with the one stamped 1 fitted in No4 cylinder, the injector stamped 2 was fitted in cylinder No3, the injector stamped 3 was fitted in cylinder No2 and the injector stamped 4 was fitted in cylinder No1.
So the question is I guess, were the new injectors coded to the ECU, and if so, where they coded out of sequence?