XF EGR Valve! If you own an XF read this!!
Most of you probably don't know (like I didn’t) but the EGR Valve has to be cleaned at least every 35,000km's most people don’t clean it, my EGR Valve had never been cleaned, the other day I took it off when I was trying to solve another problem, and it was completely clogged and blocked up with carbon, and exhaust emissions....I cleaned it, and then put it back on, and the engine is so much smoother! It idles like it was new, and the acceleration take up is so much better! I couldn't believe it, but she seriously goes so much harder...especially off the mark....it makes sense too, as the egr valve is responsible for sending any non burnt emissions such as nitrogen back into the plenum chamber and reburning it, and if its all clocked up it means that this process is slowed down, and the quicker you can get the exhaust out the better.....
So if you own an XF clean the EGR Valve, its so worth it!! You will notice the difference straight away! If yours is really blocked like mine was, you will see the difference....
To clean it properly, do this:
Take the egr valve off the plenum chamber/rocker cover (on efi models) by unscrewing the exhaust inlet pipe, then taking the two valve retaining bolts off, the egr valve will now be free. If the little egr valve "manifold" is really blocked/dirty then the best thing to do is soak it in petrol over night, to do this unscrew the actual valve housing from the manifold cast with a flat head or mini spanner, which ever suits you. Then just soak it over night. When that’s done just simply scrap all the gunk out with a small flat head screw driver. Once its all clean, its just a matter of getting some gasket paper and cutting your own gasket out and using some former gasket silicone to place between the gasket and surface. Remember the manifold and valve has a little gasket between it, with the three little screws. The manifold and plenum chamber join has a double gasket, if you are using .08mm gasket paper. Remember to thoroughly clean the two surfaces which are going to have the gasket, its just a matter of scrapping the old gasket off with a flat blade screwdriver.
I’m not sure if you can get ready made gaskets for the egr valve. I always find it easier to just make your own with the gasket paper.
If it isn’t badly clogged then you don’t need to detach the manifold from the valve, just use a mini screw driver and gently scrap it clean, making sure not to scrape the valve seat, in the middle hole, as you may damage it. You can even soak the whole unit over night, just fill up a container to where it will only cover the manifold and wont touch the valve, as I don’t know what petrol could do to that kind of rubber.