There's a better one than that Geoff shows all the block sensors in one pic, helps to see exactly where it is.

Post the link please Geoff, engine sensors, it shows it's position really clearly.

Does the gasket look like it's been replaced several months ago to cure a leak in it's near past, check the other bolts for spanner rash

Best to replace the studs while it's off, they maybe stretched and ready to give up soon.
Exhaust studs ( hot side) are different to inlet side ( cold side).

Went to a very large world wide company the other week, their job is to get an engine from the manufacturer and make sure it meets their spec required / desired, they strip, measure everything, then develope an additive specifically for that engine, test measure, test measure, until it meets it. The...

I thought toilet roll and kitchen roll was double sided, but I stand corrected as I only use one side.

Remove the crankshaft sensor (one bolt) low down on the front of the engine, don't lose the O ring, there will be a little bit of oil messing up the sensor, wipe it's face and the socket out with a tissue and replace.

That's what we like, good explanation and pics, better than my waffle.

Yes, inside the pipework and filter housing

1800 revs is about when the turbo kicks in, take a good look round the small pipes and actuator that controls it's operation, also check the air filter housing and pipework as this makes a great winter nest for mice.

Enjoy your trip, it's the air con drain.

Check the small dia vac pipes that run from the vac pump to the cold start vac switches / solenoids and then on to the EGR solenoids. Any problems with the old vac pipes collapsing when warm /hot or the solenoids not opening to let the vac through could hold the vac when it shouldn't or letting it t...

I think the one-way valve is the basic floating steel ballbearing type which corrode and stick

Not many know about the valves, and from memory don't think the drawings indicate the inner one way valve, let us know if it makes a difference.
I've always wondered if these getting blocked contributes to some problems blamed on the fuel pump leaking back when the engine is stopped .