Did one of these a while back with the intention of making a guide, and I was speaking about it today so decided to throw this together in case it is useful to anyone thinking of doing it themselves. I did it without removing the pump, access is very tight but it is definitely doable. I realise for some unlucky people the solenoid will be seized in place and may require the pump removing so it can be extracted. If you don't like working where your hands barely fit and get stuck a lot, and you can't actually see what you're doing, I would advise giving this a miss.
Symptoms of a faulty timing solenoid on the bosch vp44 pumps is a constant diesel knock, which is especially pronounced on acceleration, and the ecu logging P0149 and P1564 codes. These codes can also be generated if the pump timing is out on the sprocket.
You will need:-
Good quality T30 torx bit
Decent socket set
An assortment of socket extensions and wobble bars a must
Soldering iron
Electrical tape
You may want:-
Wire soldering clamp (makes soldering the wires together a lot easier)
1. Isolate the battery by disconnecting the negative lead
2. Working from the top of the engine, remove the inlet manifold. There are 9 bolts attaching to the head (red) and 2 more (green)
3. From underneath, you need to remove the starter motor. First, disconnect the wires going to these two terminals on the starter solenoid
4. Then disconnect the two bolts holding the starter to the engine (the one arrowed red is a rough location, its at the top in line with the bottom ones) and withdraw the starter motor
5. Just to get it out of the way, unplug the wire from the oil pressure switch. It should allow you a bit more room
6. Using a T30 bit and whatever wobble bar works for you, remove the 3 red screws attaching this bracket to the pump.
Then remove the two green ones (13mm I think) and withdraw that part of the bracket
7. Then remove these two yellow bolts holding the rest of the bracket to the block (yellow in step #6 too) and withdraw the rest of the bracket
8. Now you should have access to the timing solenoid.
9. Undo the two T30 screws (yellow) holding it to the pump, and carefully prise it out. I used a couple of thin screwdrivers under each lug an prying both at the same time. A small amount of diesel will come out when the solenoid is released. Once you've got it out, cut the wires to the solenoid as close to the solenoid as possible (where the red arrow is)
10. On your new solenoid, cut the connector that comes with it as close to the connector as you can, keeping as much wire on the solenoid as possible.
11. Strip back the sheath on the wire and "tin" it with solder. Basically you want to have the wire as easy to connect together as possible. Tinning is where you cover the copper ends of wire with solder so they are protected and easy to work with. If you're not great with a soldering iron practice on some scrap wire first, and check this out http://www.instructables.com/id/Strip-a ... ike-a-Pro/
12. Do the same on the end connected to the pump, that you cut the old solenoid off before (green). You'll probably want to cut back the protective sleeve back a bit so you can get to the wires. Take your time, its quite fiddly trying to do this whilst leaning into the engine bay. My timing solenoid came with heat shrink wrap insulation, so slide one of these on each wire before you connect them together (green)
13. Underneath the vehicle, fit the new solenoid, and thread the wires up round the back of the pump, so you can reach them at the top.
14. Carefully solder the wires from the pump to the ones on the solenoid. It doesn't matter which way round they go. It is quite tricky to do manually, but I managed it. You can get wire soldering clamps, which basically have two clamps that will hold the wire for you whilst you solder. An assistant might be useful to hold the wires if you're struggling without.
Once they're connected slide the heat shrink back over the solder and, using a lighter or even your soldering iron (don't use the tip though because it will contaminate it) heat the heat shrink till its covered the join. Hopefully should look like the pic. If your soldering is too wide to slide the heat shrink over, don't worry too much. I'd just make sure i'd wrapped each one very securely in electrical tape. Just make sure its not gonna short out on anything.
From now on its pretty much a reversal of the removal, starting at step 7 and going backwards. When refitting the starter motor make sure you get the wires the right way round. Should be the two big red cables from the battery and alternator to the slightly bigger post, and the smaller cable (which I think has an integral nut) to the smaller post.
Also note that you have to have the top bolt in the starter motor before you offer it up to its hole, or else you'll never get it in. And don't forget the earth cable to the bottom bolt.
Hopefully this will be of use to somebody.
Danny