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.
The carby and efi models both have one, they are exactly the same, except they are in different locations....they both operate through the solenoids, which creates the intial vacum.
The egr valve has a circular valve, with a orange rubber valve incased in it, it has a small connecting manifold...its actually quite hard to explain, if someone has a scanner, they can scan a pic of it, from a gregories manual or a photo froma digital camera (none of which i have).
The egr valve on efi engines sits on top of the rocker cover on the other side of the plenum intake tubes and injectors.
On carby models it sits on the side of the engine, im not sure which side, as I am going from a picture, im pretty sure its the distributor side, so most likely the right side. (if facing the bonnet)
so the EGR valve is in the gregorys manual then...im assuming it doesnt say much about it though as i have found those books to be useless on many other occasions. if its in the book with a diagram of where it is i will find it and follow your instructions!
yeah gregories manuals arent the best...i dont use them too often...but they do come in handy....
page 254 has the egr valve on carby models....and page 257 has the efi model....thats in the emission control of the gregories manual...a recent reprint too.....so pages may vary if they have added anything in, which they sometimes do as new problems come out....
Back when they were released in the mid 80's 'wheels' dyno'd a NZ and Aust car together. NZ spec cars didnt have an EGR valve and made 5fwkw (5%) more.
Yeah thats exactly why when you clean a blocked one the engine runs smoother and has better throttle....I never said it had more power, I said the throttle take off is better.....and it is on mine.
fordmuscle_83 is basically right. The EGR valve works on vaccum which means when you mash the throttle the valve closes off.
The valve doesn’t close off, the valve opens up more, the egr solenoids create the initial vacuum, the more you accelerate and therefore create more rpm then the more the valve needs to open to compensate for more of the unburnt emissions/nitrogen and let more into the plenum chamber…..
Recycling exhaust gas doesn't reburn (hardly anything at all). It fills the combustion chamber with inert gas to minimise part throttle and cruise emissions and help fuel economy slightly.
It does burn, it burns about 15% of the emissions which is what the egr valve is there for. It reduces the peak combustion temperature of the emissions by reburning it, which is the causes of poisonous nitrogen. it doesnt help fuel economy at all, it effects the air/fuel mixture to an extent where a little more fuel is used as opposed if you didnt have a egr valve on your xf.
i valve opened one up and left the other one blocked, should i open the second one as well?
In the actual mainfold that connects the valve there is two holes, the actual manifold on the engine only has the one hole.
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