Hi. I get the occasional random ECU reading that seem to point towards the EGR and throttle. Have looked around on Briskoda and decided I'm going to take a look at a few things and see what's going on. 

 

I want to remove and clean the EGR, throttle body, inlet manifold and lambda/oxygen sensor. As far as I can tell I need to remove the throttle body to get the inlet manifold off. My main question is that I can't see to find a definitive answer on, is if I leave the throttle body connected up, but remove it so I can clean both sides and take the manifold off, will I need to mess around resetting things? As far as I can see you only need to if you disconnect. 

 

Also, just for easiness sake, does anyone have the codes for any gaskets I might need? Or are they generally reusable (I know it's best to replace but if it's in good condition would it be a problem?)

 

Cheers.

Don't bother touching the Lambda probe, if you leave the TB connected you won't need to re-adapt it, manifold is o rings not gaskets, usually best to replace them, spray the MAP sensor with contact cleaner but don't poke it, clean out the EGR pipe using a bicycle gear cable and some carb cleaner.

I think, but am not 100% confident, that as long as you don't switch the ignition on while the throttle-body (or EGR valve) are disconnected, then there shouldn't be any need for adaptation after reconnection. Neither TB nor EGR has any local 'intelligence', I believe, so if the ECU isn't awakened during their 'absence' then it cannot know that they were ever 'not there'. Just speaking from my theoretical understanding, may be something I haven't considered or understood.

 

Find part numbers for o-rings etc. Somewhere like here:

http://www.partscats.info/skoda/en/?i=cat_vag_models&brand=sk

Edited 29 January, 201511 yr by Wino

If you take the Throttle body off (i leave it plugged in) you will see the vertical tube (with two holes on the sides) just below the throttle body, this is the EGR feed tube, it travels downwards then bends 90 degrees away from the engine block (non removable). At this point there is a flange and another pipe (EGR Pipe) joins, This pipe is routed above the gear box and then joins onto the bottom of the EGR. 

 

I usually take the EGR pipe (from the valve to the intake) off, remove the EGR and remove the throttle body and give everything a through clean. the hardest one is the EGR feed tube in the intake as you cant get into the tube that easily.

Both EGR and TB however will need re adapting once cleaned. If there is dirt/debris blocking the component operation the adapted values will have changed to compensate for the dirt. If you clean it out it needs to be reset. Channel 060 for the TB and 074 for the EGR.

Edited 30 January, 201511 yr by Tech1e

That would be the "something I haven't considered or understood" above.

 

On the other hand, if you don't need to see instant 'ideal' behaviour, it seems to me that if the ECU can adapt itself to dirty components all on its own, it ought to be able to adapt to clean ones again without help?  Don't know about the timescale on that though.

Thanks for the replies everyone.

Just out of interest sepulchrave, why should I not bother with the Lambda? I've had a look and found the gaskets etc I would need, I'm just unsure of readapting. Was hoping for some fairly cheap maintenance! Is it generally an expensive thing to have done? Makes perfect sense though tech1e that it'd need doing either way. Presumably what winos suggested also makes sense. Would it be a painful process allowing the TB and EGR to readapt themselves?

I've seen a few tutorials around about resetting things by some process of unhooking the battery then leaving the engine idling for a certain amount of time etc. If this actually works what is the difference? Does re adapting it with a vag.com set it to ideal values rather than just resetting it?

Thanks for the help, I'm not new to working on cars but this is the first car I've had with more sophisticated electronics.

I think what was meant is, "is the car logging lambda probe faults - if so replace it     if car is not logging any lambda probe faults then leave it well alone".

 

From my experience of only one BBY engine, the EGR valve and its long pipe will be clean or clean enough, where the problems seem to be are in the EGR pipe port on the TB or inlet manifold due to the convergence of hot exhaust gas and oily fumes - this stuff results in tarry stuff blocking that port and only that port area. I eventually removed the MAP sensor and replaced it with a used one - though I should really now that a year of so has passed refit the original one as it is an updated version of the used one I fitted. Expect to find the inlet manifold covered in tarry deposits - I left that stuff alone, though ideally it should/could have been cleaned out if I removed the inlet manifold. To get the TB off, you might need to remove the EGR pipe, maybe at both ends and if so remember that there is a support clip under the thermostat etc lump. I listed all gaskets used in that job a year or so ago, so maybe search for similar topics.

 

One last bit of advice, what ever you do, I suggest that you do not try to force the throttle valve open as that will annoy the linkage.

Edited 30 January, 201511 yr by rum4mo

Cheers rum4mo. I did get a Lambda sensor fault log over half a year ago, but wasn't sure of it's accuracy since I've never had it again.

As far as I've always known EGRs in petrols are usually kept clean, but have seen conflicting information about if they should be cleaned. I can see why the pipe port would get the most build up. BBZ have the EGR on the exhaust manifold at the front of the engine, so would that mean I could just get the gaskets for the pipe and leave the EGR in place? 

 

Will definitely not be move the throttle butterfly, hope to be able to clean around it without needing to move it anyway! 

 

Will have a search for your post for all the part codes. 

I disconnected the EGR valve pipe at the valve and at the TB, I'm not sure if that was necessary, that pipe is quite long and stiff, the support clip under the big plastic water pipe lump, it is quite tricky to locate, so once you have felt where it is it will be down to feel and a longish 1/4" extension and socket. The EGR valve is in the same place on the BBY engine, it could be with the support clip bolt removed and the TB end of the pipe unbolted, you can get enough movement to get the TB assembly off the manifold.  I had other issues with my BBY engine, had found a new unwanted EGR being sold on ebay, so grabbed it - so that meant using it, needless to say the old valve was okay and clean, I seem to remember the EGR valve is mounted on to the engine block via an adaptor, and these gaskets are probably not reusable - the EGR valve pipe ones though are just metal so should be okay to reuse although I played safe and replaced any gaskets I came across, as said already, the TB one is just an O-ring and is okay to reuse and it should remain in its groove in the plastic inlet manifold.

Cheers mate, very helpful! I've found the pipe gaskets from skodaparts for a couple of £ so will just replace them.