Intake Carbon

[cammmy]

Hi All, I know there are various discussions about this, so I figured I may as well put the bore scope to work.

I noticed in the workshop manual that removing the intake isn't a big job and also that all the replacement gaskets are only £20. Since I have an air compressor, I figured I may as well look at doing my own walnut blasting.

I just popped off one of the throttle bodies and stuck the scope down the ports I could get it into. As you can see, it's not terrible but there is definitely build up. I may do the job anyway as there are lumps in there that I wouldn't want to send through the cylinder . The car has about 90k miles and I don't have any record of this job ever being done before.

Is there an easy way to manually turn over the V10?

Also, I thought the intake on these had a flap system in them, or is that only the S6? There's nothing like that inside mine.

[IanH755]

Similar to mine at 96k miles, the Forced Induction from the turbos keeps the back of the valves way cleaner than the RS4 and other none-FI cars but eventually you'll get some sticking.

MRC did mine and this is what mine looked like before and after -

[cammmy]

Can't see the images mate.

To answer my own question. The flaps are in the lower manifold, not the upper.

Step one of operation "I should have left this alone" complete:

The hoses at the back were a pain to get off the manifold.

Looks like the lower manifold has to come off as well. If the injectors are easy to get out after that, I might send them off for a service since I'm in there anyway.

[cammmy]

Oh also, for anyone taking off the manifold. I highly advise using whatever combination of extensions and adapters are required to get an impact gun on the bolts holding the intake down. They are made of cheese and extremely easy to round with a ratchet. Especially the ones at the back as access is not good. I had one start to go on me. Luckily there was enough left for the impact to do it's job.

I've gone ahead and ordered a VAG injector removal/installation kit. If anyone is looking to pull their injectors, it'll be available. Maybe just with a deposit so I an replace it if it never gets back to me.

[cammmy]

Got the lower intakes off. Some of the injectors cameout by hand but I'll wait for the tool to do the rest. Don't want to break the plastic. I couldn't believe how much grit gets down around the injector bodies. Some of the valves are definitely a bit grotty.

[welwynnick]

Oh also, for anyone taking off the manifold. I highly advise using whatever combination of extensions and adapters are required to get an impact gun on the bolts holding the intake down. They are made of cheese and extremely easy to round with a ratchet. Especially the ones at the back as access is not good. I had one start to go on me. Luckily there was enough left for the impact to do it's job.

I'm curious how an impact driver will help in that situation? I have an impact driver, and sometimes it's invaluable, but it usually gives whatever it's driving a hard time (and adding extensions and adapters tends to negate the benefit of the impacting).

Nick

[cammmy]

I find impact drivers much less likely to either round or shear a fastener. I use a pneumatic one so I can easily start at low power and wind it up with the trigger.

[cammmy]

So, to use the port adapter you really need an extra long blasting tip that you can get down into the port and aim. They only seem to be available from the states. Otherwise, you end up getting the walnut shells everywhere. I'm waiting on some brass pipe brushes to arrive so I can get around the back of the valve and the very edges a bit better but here's the first one.

Also, unfortunately the plastic injector bodies turn to brittle toffee, so even though I have the proper tool, 4 or 5 of them ended up with prices broken off. I'm hoping the injector place will be able to salvage them in some way, rather than having to replace them.

[cammmy]

I've ordered a pipe bender and some 1/2" 3mm wall aluminium tube (only thing available in that size/thickness). That should let me make some extended nozzles of varying shapes. I'm not too worried about it being aluminium since it will only be used with walnut shell, which is super soft.

[cammmy]

So R-tech just called about my injectors. Apparently one is down on flow but worse than that, several are leaking. I would never have guessed. The car is a bit lumpy for a short period on cold start but other than that, it drives fine. So even though the carbon buildup isn't as bad as the N/A cars. This may well be worth doing anyway so you can get your injectors serviced. Mine has about 90k miles, so there are others with more than that out there that have probably never been looked at.

[cammmy]

Injectors all serviced. Ended up being £200 for all 10 including swapping out the plastic filter baskets for steel. It seems stock ones can dissolve and take your engine with them.

I haven't gotten them back yet but so far, happy to recommend R-tech.

Thankfully they didn't think the broken plastic on the housings necessitates replacement. They said whilst they can't make any guarantees, they've seen much worse and they didn't leak on the flow tester.

[cammmy]

Update on turning the engine over. With the injectors out and no compression, by far the easiest way is a t50 in the alternator pulley and turn it with an extra long aviation ratchet spanner. May be possible with compression but I would be careful.

[cammmy]

Well, all done. Haven't driven it yet but I pulled the battery to clear any trim on the fuel table and it's immediately smoother on cold start. I need to play musical cars tomorrow to get it out for a drive.

All in all, not the worst job but you need to be careful and methodical. I can see why it costs £450. I spent about £100 on gaskets and it would probably be most of a day even with experience and all the tools to hand.

[Daversc6v10]

Hi Guys,

I'm trying to remove the lower intake manifold, I've removed all nuts and bolts, is it now just a matter of pulling them upwards?.

any help would be very appreciated.

Thanks Dave