D3 or 4?

Pretty much every job you list there is diy stuff Main suspension part that dies is front lower arms, done mine twice now. Brakes are simple, they are just like any other car on the road, with the exception of the handbrake set up. Air susp warning is most likely a small leak, air bags would...

If you drill it, first use a drill bit that is the exact same size as the hole, just drill enough to mark/dimple the bolt so you can then swap to a smaller drill bit and be sure you are bang in the middle. 4mm drill bits are my favourite starting size, small enough to be make easy progress, yet...

The 200 in my s2 is as a dry as a bone, 90 one less so!

I would say it is drawing in a small amount of air from somewhere, maybe worth turning the ign on and listening for the fuel pump running until it stops (10 secs ish), try this three or four times before starting the engine. Iirc the fuel filter heads used to go porous inside?

Easy enough to check if you stick up a good close up picture of the injector pump. If you remove the tapered boost pin you can see where the pin has mainly been running.

If it was rear main it would be leaking out of that wading hole. As said twice above, them 1/2 moon seals are dog shti, you need new ones fitted with blue hylomar.

If you are local to me I might have some in the garage.

They are at work 20 miles away, they are just the small long nose variety with jaw teeth ground off leaving a rounded profile so it does not damage the pipe.

If it is splitting then the pipe has had its day, this is why we were doing the recall years ago as where the pipe stretches slightly to get it over the barb it was developing hairline splits. It is just nylon air brake pipe, available at any commercial motor factors and of course ebay etc.

Old W reg volvo, 2 million plus on the clock, so not new and easy to work on. Old fitting with new pipe Old fitting with the original pipe which I had to cut to get the bracket off.

The nylon pipe is great stuff, lasts for decades on air and fuel systems. Real tough gear, I use modified mole grips to crush the pipe so I can isolate areas to work on compressed air systems. I use it all the time at work, and never use heat as it shags it. A good grip, some spit on the barb...

My first port of call would be an air chisel with the chisel bit cut off flush. If you try and punch it out like a pansy what will happen is the end of the bolt will expand and get tighter in the hole. Are you using 6 sided sockets? Next size socket down can help a lot, obviously will need...

I used to weld loads of cars years ago, terrible job, still do the odd one when I have to. Try and keep to the heavier stuff as it is way easier!

Not good. Stick some pics up.

Normal, mine did it for 50k miles and a few years with zero issues, might be some vids on youtube?

EDC injection pump.

How much freeplay on the master push rod? Is the flex okay?

I think people have fitted them behind the front seats on that flat panel, that way all the smelly bits are outside the living space. I fitted a cheap chinese one to our boat, have to say I was impressed. The usual named makes are better quality, but they are also several times the price.

I had the same with a 300 once, might have been because I fitted the head gasket upside down/back to front, allegedly! 200tdi you cab reuse head bolts up to 5 times so long as you measure them for stretch beforehand, not sure on the 300 though?