Well as much as I wanted it to be a dodgy fill up or a bunged up filter I knew it was the injector loom that was giving up, so I bit the bullet and got down to changing it this weekend. I had a good search on here but couldn't find a "how to" guide so here it is - I also thought it was time I gave something back to this forum as I'm forever using it as a reference manual
Part number 045 971 600 £57.00 inc VAT (August 2012 prices)
Summary of work required: remove rocker cover, unplug harness and replace.
Caution: When removing and replacing the windscreen wiper (I'll explain later) BE CAREFUL. There are plenty of posts on here about cracked windscreen from the lightest of touches from the wiper arm to the glass.
You need to remove a few items to get to enough room to remove the rocker cover (should that be camshalft cover?)
Wiper arm
Washer heads
Air intake
The removal of these are covered in pages 5 to 7 of the TDI cylinder head pdf attached
Once these are removed un bolt the rocker cover. the bolts at the from and on top are obvious. There are, however, three at the back that you will have to remove blind. Image 294 shows a 10mm 1/4" socket on a screw handle attached to the bolt in the middle, the one to the left is no too bad but the one on the right is difficult to get to as there is pipework above preventing vertical access. I used a flexible connector on a 10mm 1/4" socket but a shortish extension turned with molegrips might work.
Unclip the cambelt cover on the left (clips back and front) to enable the rocker cover to release vertically. Never prise of with a screw driver but hit gently with a soft faced mallet or similar if it seems stuck. The gasket is reuseable, so be careful, wipe clean and reuse!
The harness is now visible (image 295)
The harness is held in on the right hand side with 2 10mm bolts. You might find the one you can see is captured behind the bracket for the pipes which run in front of the rocker cover just un bolt it to fully reveal the bolt you need to get at.
Unclip the harness from the injectors and withdraw to the right. You will need to compress the clips so that it slides out. I found one ofthe clips needed to be compressed on both sides to go through the machined hole in the head.
As they say in all good manuals - refitting is as above in reverse!
On inspection of the old harness I could see that one of the wires was pinched and had gone through the insulation - so be careful not to replicate this!
Good luck, take it easy and be methodical, give yourself 4 hours and it'll only take two.
On reflection I'm not sure the wiper arm has to be removed but you do need to get under the trim to access two torx screws which hold the air duct up. Wiper arm removal can be a disheartening first step if it doesn't want to play ball, if so you may need a puller.
Part number 045 971 600 £57.00 inc VAT (August 2012 prices)
Summary of work required: remove rocker cover, unplug harness and replace.
Caution: When removing and replacing the windscreen wiper (I'll explain later) BE CAREFUL. There are plenty of posts on here about cracked windscreen from the lightest of touches from the wiper arm to the glass.
You need to remove a few items to get to enough room to remove the rocker cover (should that be camshalft cover?)
Wiper arm
Washer heads
Air intake
The removal of these are covered in pages 5 to 7 of the TDI cylinder head pdf attached
Once these are removed un bolt the rocker cover. the bolts at the from and on top are obvious. There are, however, three at the back that you will have to remove blind. Image 294 shows a 10mm 1/4" socket on a screw handle attached to the bolt in the middle, the one to the left is no too bad but the one on the right is difficult to get to as there is pipework above preventing vertical access. I used a flexible connector on a 10mm 1/4" socket but a shortish extension turned with molegrips might work.
Unclip the cambelt cover on the left (clips back and front) to enable the rocker cover to release vertically. Never prise of with a screw driver but hit gently with a soft faced mallet or similar if it seems stuck. The gasket is reuseable, so be careful, wipe clean and reuse!
The harness is now visible (image 295)
The harness is held in on the right hand side with 2 10mm bolts. You might find the one you can see is captured behind the bracket for the pipes which run in front of the rocker cover just un bolt it to fully reveal the bolt you need to get at.
Unclip the harness from the injectors and withdraw to the right. You will need to compress the clips so that it slides out. I found one ofthe clips needed to be compressed on both sides to go through the machined hole in the head.
As they say in all good manuals - refitting is as above in reverse!
On inspection of the old harness I could see that one of the wires was pinched and had gone through the insulation - so be careful not to replicate this!
Good luck, take it easy and be methodical, give yourself 4 hours and it'll only take two.
On reflection I'm not sure the wiper arm has to be removed but you do need to get under the trim to access two torx screws which hold the air duct up. Wiper arm removal can be a disheartening first step if it doesn't want to play ball, if so you may need a puller.