Important:- I would strongly advise that you do not undertake this task when the engine is hot. I found that the fuel return lines bend when loosening the banjo bolts. Luckily the lines didn't split and i was able to bend them back to their original shape but it was extremely awkward and risky.
Job time – 1 hour 10 mins
Disassembly (40 mins) - may take longer if in a bad way
Cleaning (20 mins)
Reassembly (10 mins)
Tools required: Socket set 10mm, 12mm, 14mm and 14mm spanner. Also need flat head screw driver for scraping and some WD40. Lots of rags/tissue paper. Wire coat hanger or similar strength wire and cutters. Vacuum cleaner.
Parts: Copper washer (injector seal) and O-Ring (half way down the injector). Part numbers: 11176-51010 and 96721-19017 respectively. This is for a 2007 IS220D.
I reckon I saved about €400 (£340) by doing this myself (from the prices I have seen on this forum).
Remove wire harness clips (2) on wire harness that runs over the injectors. Both broke on me as they were fragile from heat over the years. Didn't bother replacing
Remove wire harness nuts (2) 10mm socket
Disconnect all four injectors' electrical connections (don't worry about mixing them up, they can only reach their own injector)
Lift wire harness up a little and move to the left out of the way
Remove bolt (1) 10mm securing one of the fuel lines. See yellow arrow above
Remove back bolt (1) 14mm on back on the Fuel Leakage Manifold. See blue arrow above. This is tricky to access - I used a ring spanner and could only get about 1/12 of a turn each time. Watch out for the double washer - it can easily fall down into the engine bay
Remove the securing bolt (1) 12mm on the Fuel Leakage Manifold. See green arrow above - hidden behind the electrical connector on cylinder #1 in the photo.
Remove bolts (4) 14mm holding the Fuel Leakage Return Pipe above all of the injectors. These bolts secure the pipe to each of the injectors (there is a hex head in each)
Lift off the Fuel Leakage Return Pipe
Protect each of the fuel points with tissue paper
Remove bolt (1) 12mm on large clamp holding the injector in place
Remove clamp - once this is removed nothing else is holding the injector in place
Remove injector. It will not lift out easily so use some leverage. I used a screw driver and worked my way around it. I also used a small bit of WD40. It took a few minutes but persist. It may work trying to twist it before extracting to loosen it
Remove copper washer down in the injector port. It is about 130mm down and sits on its own shoulder. If it is in one piece (which it should be) it cannot fall down in to the chamber below. I used a wire coat hanger for the wire to pull out the washer. I bent a short 90 degree bend at the bottom and cut it at an angle to leave a sharp point. See top "tool" in the photo below. This allows you to get in between the washer and the shoulder it sits on. Keep at it until it loosens. A small bit of WD40 helps
Clean injector (and remove the old o-ring), clean injector seat, clean injector port (as far in as possible). I used a flat head screwdriver to scrape away the black stuff. It flakes off. I used the second tool in the picture below with some tissue wrapped around the bottom, and stuffed it down into the injector port. This allowed me to scrape away any of the dirt and let it fall into the port. When I was done, I taped a short piece of garden hose onto the end of the hoover and sucked out the gunk that had fallen in. I pulled out the tool and it cleaned the inside of the port as it was withdrawn
Add new o-ring and copper washer. I applied some grease just to hold the copper washer in place as I inserted the injector back into the port.
Repeat the reverse process from "remove clamp" back up to securing the wire harness. However, it is advised that the fuel line bolts (banjo bolts) are only hand tightened until everything is back in place - then tighten away (credit @kenwoodIS)
Prime the fuel system
New and old washers and o-rings. New on left!
Injector cleaned and washer and o-ring attached.
Cleaned injector seat and port.
Damage to Washer: