I posted this a while back but I forgot to post in this section. I've added a few photos at the bottom as well.
First off, I am not a mechanic so my terminology may annoy some of you!
I did this as i was getting a lack of power at about 2500revs mainly in higher gears. It has improved dramatically. Fuel efficiency seems to have improved but only slightly so I can't say for sure.
For this guide, I refer to right and left as you stand at the front of the vehicle looking into the engine. I know this is not the norm so apologies if confusing. Front refers to the front of the car as standard.
Also, the elec. connectors are the biggest pain in the &%$£. Trying to squeeze the clip and pull at the same time is so difficult as they are usually well stuck in place being nine years old! Don’t give up!
Job time – 10 hours over two days (I didn’t have a guide so hopefully you will do it faster – it would take me about 6 hours if I did it again)
Set up tools, bench, laptop, etc. (1 hour)
Disassembly (5 hours)
Cleaning (2 hours)
Reassembly (2 hours)
Basic tools are required but just having a good socket set is very important. Not necessary to jack up vehicle but would help. I drove the front wheels up on 3inch blocks.
This is the order I did it in, you may want to do it a little differently. I include headings for the most part but in general this order worked well.
Here we go!...
Remove primary engine cover
Remove RH engine cover
Remove LH engine cover
Remove front engine cover
Remove under engine covers (x2)
Disconnect battery terminals
Remove battery horizontal support brace
Disconnect the electrical connection on the LH side of the battery cover
Remove battery cover
Remove base cover of battery
Remove battery vertical support brace
Remove control module under battery (x3 bolts – long one goes on RH side)
Disconnect 3 elec. connectors on control module
Remove bottom battery case (x3 bolts)
Remove EGR pipe and gaskets
Disconnect EGR elec. connector
Remove EGR valve
Open radiator cap and drain ***** (have bucket ready to take ~5 litres)
Remove air intake duct above radiator
Disconnect inlet and outlet pipes of radiator fluid reservoir tank
Remove reservoir tank
Disconnect fuse box wire harness clips (x2)
Disconnect common rail front end elec. connector
Disconnect common rail fuel supply hose
Disconnect common rail rear end elec. connector
Remove wire harness support bolts (x2)
Disconnect EGR valve rear end elec. connector
Remove five wire harness clips (red arrows)
Remove harness support (green arrow)
Remove sponge adjacent to EGR valve
Remove bolts (x3) on water pipe (blue arrow) below EGR assembly
Remove clip at front end of pipe and slide hose off
Remove vacuum hose (small) from water pipe (underneath)
Remove elec. connector under vacuum hose & remove clip also (hard to see but you’ll know it has to be disconnected)
Push hose assembly out of the way – towards battery area (no need to fully disconnect)
Air Flow (Throttle) Assembly:-
Disconnect three elec. connectors on air flow unit
Remove bolt on air flow unit
Remove common rail bolt (x2)
Remove common rail fuel lines
Protect (tissue) the common rail connectors & ports
Remove common rail and keep clean
Disconnect vacuum hose from inlet manifold
Remove inlet manifold upper stay bolt (it’s a vertical support that can be hard to see)
Remove air flow pipe to inlet manifold (1 clip also) (difficult to remove for me but keep twisting and pulling – there is a lip to overcome)
Loosen inlet manifold lower stay nut (very difficult to access – hard to even see. This was the most awkward part of the whole job. You should really disconnect for easier access but it would be impossible to get it back on – loosening and pushing it aside was fine for me) See diagram below.
Remove bolts (~x9) on intake manifold
Remove intake manifold
Clean inlet manifold – I used a power hose, carburettor cleaner, screwdriver for scraping & kitchen paper.
Clean inlet ports – as above but I used a hoover continuously to prevent as much carbon as possible entering the valves/cylinders
Reinstall in reverse – much easier than disassembly!
Prime the fuel system.
Photo 1 - Inlet ports exposed after inlet manifold clean. Of the four ports showing, the first has been cleaned mostly, the second is as found, and the third and fourth have some cleaning done. Highly recommend using a hoover if scraping any carbon from here. Otherwise just coat with carburetor cleaner and wipe away with a cloth.
Photo 2 - Inlet manifold removed. Condition hard to see but constriction increases further into the ports.
Photo 3 - Inlet ports - two untouched and two partially cleared.