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Discussion Starter · #1 ·
I have been suffering from a slight rough idle when engines first fired up so thought id check out the intake system and EGR valve.

Firstly my cars just gone past the 120k mark so i knew things wernt going to look nice.

firstly i removed the EGR valve, quite an easy job, got it off in about 15minutes and this is the state of it inside.

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As you can see from those pictures above the valve was badly clogged up restricting / disturbing air flow, This is very sludgy and then sets like charcoal in some places.

So took a while and scrapped it all out, sprayed around it with brake cleaner too. and this is how it is now.

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Whilst the valve was off you can see straight into the inlet manifold and things in there isnt any better. . So my next plan of attack is to have the complete inlet manifold off and clean it all out. Next week maybe.

No more rough running whilst cold anymore [y]
 

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thats a good job you've done there! looks pretty manky! i keep meaning to do mine, but never do!

there's a write up i've seen on vortex that has pictures and everything on how to strip down the inlet manifold and clean it all.

did u need to replace and brackets or anything??
 

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Discussion Starter · #3 ·
Cheers, if you need any more advice when doing yours just let me know. More than happy to help.

There is a rubber seal that fits between the valve and the inlet manifold ,probably worth replacing but mine was ok, i intend on replacing it once ive cleaned out my manifold.

And theres a thin gasket that sits on the exhaust pipe to the valve, again mine was ok but i will replace it later.

Apart from those nothing else. [Y]
 

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Nice work.

I've got the egr 'o' ring, both egr pipe gaskets and an inlet gasket sat in the garage waiting to do this. My 115 is at a touch over 130k now so MUST need doing. Did yours smoke under a heavy hoof ? If so, is it better now ? I get a proper soot storm out of mine if I hoof it,which I do, a lot.

Been thinking of ways of cleaning the inlet manfold as it is a complex shape and plastic. I dont want to damage it and may simply get a price for a new one ?

If you beat me to it, please post up on how you get on with the inlet clean and post a few piccies.
 

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Discussion Starter · #6 ·
My car has never smoked as such, just usually gave out the odd puff of smoke when you boot it but thats pretty known on every diesel, + mines remapped too

What made me do it is i started my engine from cold and watched it, it looked as if it was misfiring without the miss. The valve was switching as you can see the shiny mark on the "pole" through the centre, just was restricting air and disturbing the way it should flow.

Could be quite tricky to do the manifold , i was thinking of getting something that looks like a little chimney cleaner, you know what i mean? Or at work ive got this Die cutter with a flexible extension, will try and see if i can get a little rotary wire brush end on it.

If i was you Ct.p i would spray some release oil on the exhaust pipe end with the 2 12mm nuts, as mine were pretty tight and corroded. Then that way when you come to do it it should be simple.

Will do a guide whenever i do it.

Tools for removing egr valve. 6 + 7 mm allen keys, 12mm spanner, some molgrips or waterpump pliers for intake hose clip, electrical screwdriver (incase vacuum hose is stuck on) and large flat head screwdriver
 

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Did mine tonight.

Unfortunately couldn't take any pics though.

It wasn't quite as bad as yours looking at your pictures which is suprising as I'm at 130.5k.

I'm sure it must have something to do with the way the cars are driven, I thrash mine within an inch of it's life almost everywhere which must "blow" things through [:mad:]

As for the smoking, that I'm sure is down to the map and my heavy foot.

Also had a look at the inlet manifold. Doesn't look that difficult as I could get the allen socket on all the bolts with the exception of the far right hand one. The far right hand one is obscured by the turbo oil feed pipe, the rigid one. So with it being a work night didn't fancy it to much as I'm sure some heat shields will have to come off as well to remove the manifold itself, and no doubt it would have tuned out to be a far longer job.

Saying that, things were far from clean but acceptable in there so I think I may consider cleaning it in another 20-30k or so.

If you do clean your inlet, keep us all posted.

[edit]

The inlet is aluminium, NOT plastic. VW chose the expensive option, bless em.
 

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Discussion Starter · #8 ·
I was going to correct you on the material the manifolds made of, but my comp was playing up.

Maybe yours has already been serviced / replaced?

i thrash my car in a sensible manner but since owning my car for 6months ive clocked about 8k....but you dont know how the previous owner drove it, and once it starts building up, it can only get worse. as you can imagine the carbon build up will atract more carbon specially as its a rough surface its making.

Planning on doing my manifold in a few weeks.Id love to get it chromed / powdercoated or something, just to tidy everything up a bit.
 

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Carb cleaner spray works better than brake cleaner spray but doesn't leave that dry type finish that brake cleaner does so might be worth using carb clean first and then brake cleaner - this is what I did when I did mine but it turned out I had to replace my EGR after 7k miles anyhow so it was somewhat academic
 

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Maybe yours has already been serviced / replaced?

i thrash my car in a sensible manner but since owning my car for 6months ive clocked about 8k....but you dont know how the previous owner drove it, and once it starts building up, it can only get worse. as you can imagine the carbon build up will atract more carbon specially as its a rough surface its making.
I've had the car since it was at 70k, two and a bit years ago, I don't know how it was driven previously.

The gunk, although there was the same in the inlet manifold as it was in the egr, so I doubt it has been changed.

It was certainly worth doing just for peace of mind and like I say, if the car is still going, i'll do the inlet as well in about another 20-30k.
 

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Whats the flap in there for and whats it hooked up to, I notice it's linkage is outside?

I've run my car from 17K to 40K (2.5 year ownership) on BP ulimate. It smokes a lot less as i guess it burns more cleanly, so am I right in guessing that BP ultimate is going to cause less clog up?

Also I notice on regular BP it always smokes on start up but with Ulimate its much reduced.
 

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Trollgeddon: Is this where the egr valve goes? I've got a bit of a lumpy idle at the moment.



Also, can I ask, why do some people remove their egr valves?
 

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Discussion Starter · #13 ·
If you look at that picture, the whole EGR valve joins to the manifold just after that big circular part with the hose attached on top. You can actually see a joining bolt sitting horizontally. The part you circled is where the intercooler hose slots onto.

I believe some people disconnect them as they can limit power at certain times, also people block them off to stop this build up as you in this thread.

Running to the bottom of this valve (you cannot see it in these pics) there is a exhaust pipe leading to it. Id imagine when its recircualting the exhaust gases the valve shuts to direct it back round. Its all operated from vacuum. To be honest i need more education on how these work myself
 

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Oh right, thanks for that. So that silver circular thing on the top with the black fibre tube coming out is the egr valve?
 

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.....but, some who've blocked off the egr have reported a slight performance loss.

Also it's an emission control system.... think of the trees, the little green frogs that live in them and baby seals who's ice is melting.

Don't block it off, you wouldn't want to make a seal homeless would you ?

I reckon by you blocking off your egr, you'll make 7 frogs and 1 seal homeless, can you live with that ?

And yes, they would be those cute little green ones with big red feet.
 

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I'm not going to block it, it seems that it plays a part in regulating the reaction and I'd rather have more control over it than less. Plus, I love baby seals, even if one bite from them could take a finger off... or worse [:O]

As for them frogs, slimy litle buggers, they can take a flying leap! (I didn't mean that 'flying leap' bit as a joke, but when I read it back, I've decided I do!)
 
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