2010A8Lsport

2010A8Lsport

Has anyone experienced the flapper valves inside the intake or the secondary set leading into the cylinder heads break apart and make their way down onto the intake valves?

Sci-fi_Wasabi

I'm doing this right now, just got the intake manifold off yesterday. We should have the the same manifold since i have a 2009 a8L 4.2L, which is different than the 2004-to early 2009 manifold, as it is now in two halves, an upper and 2 lower intake manifolds.
I'm basing things off of these very good instructions in the same engine but in an S5:

https://www.a5oc.com/forums/audi-a5-...eaning-b8.html

Special tools, no, just a T20 to T30 Torx bits and metric wrenches for the fuel lines. Have various sizes of new hose claps around to replace some 1 use oetiker clamps. Some kind of mini ratchet or small L shaped allen like wrenches to get the T20 screws off the back of the Oil separator... or a 1/4 inch gear wrench and then stick a small T20 bit in it and pray it does not fall down the engine bay (I tied a string to it)

I'm just stuck on making a proper blasting wand for my pressurized media blaster

Change the figure 8 oil filter housing o-ring while you are at it.

My flaps were fine, but the vacuum solenoid controlling them had failed, which is what compelled me to do this. My car was running ok, just some rough idling which could be anything else, so i could have gotten by with not fixing it, but the solenoid is cheap, just labor intensive to get to. Most of my on removal was taking off the oil separator, and manifold adaptor, and cleaning oil. Took 1 day to remove, moving very carefully trying not to break old plastic.

If I had flap material in the valve area, i would just blow it out with compressed air... and just do a walnut shell valve clean while at it.

If the car is running ok, maybe consider just cleaning but not replacing the broken flaps given that each lower intake is $600+ per side. Might lose some fuel efficiency or performance.
But if you can find used ones, that would be nice. If you remove the lower intake manifolds, you will also have to put new seals on your fuel injectors as some will come out. Greg5OH has a video of him doing this and the tools needed.

I did buy new gaskets, 8 for the upper intake manifold, and 8 total for the two lower manifolds.

If you do this, I can look up the part numbers again.

2010A8Lsport

It almost looks like the intake could come off without touching the fuel lines? I will make up a custom gear wrench with the torx bit. Does the oil filter housing have to come off or is it just preventative maintenance while I'm in there?

Sci-fi_Wasabi

I tried to pull it out without removing any fuel lines, I could not, but I only unscrewed 2 fitting, on the the left high pressure pump and one to the fuel manifold between the two, and moved the tubes out of the way.
You don't need to take out the oil filter housing, it is just preventative maintenance involving 2 small T20 at the feet and two t50/M10 square bits to the left and back. When i took figure 8 ring out it felt like plastic... maybe it got hard over time, maybe that was a newer version, but the genuine audi one i got was flexible rubber.

2010A8Lsport

I jumped into it after work today, it all went pretty smooth except those 2 T20s on the back of the intake tube. Took me just over an hour, although I feel like getting that one T20 back in is going to be the hard part. I was thinking that I could split the intake in half to inspect but from the looks of it, it's a sealed unit.
I'll pull off the actuator tomorrow and use a mirror to check that all of the flappers inside are working properly.

The intake valves are actually pretty clean, I'm going to try the CGC intake valve cleaner spray, fill up each valve cavity, let it soak and then vacuum it out to see what kind of result I get.

Sci-fi_Wasabi

Wow, 1 hour, it took me 1 hour just to get the oil separator off.
Hey, do you or anyone else know how to crank the engine manually. rather than a nut, there is a threaded hole at the center of the crankshaft pulley... is there a particular sized bolt i can put in there to have something to turn it with? I have seen a special tool for locking it, which i don need to do... I'd rather go to the hardware store and get a bolt just to turn it.

2010A8Lsport

I've never gotten into one of these engines so I can't give any advice... I'd also like I know how as I am doing the carbon cleaning on my car this weekend.

i will search around to see what I can find.

Sci-fi_Wasabi

Ultimately I disconnected the 2 high pressure fuel pumps and the relay to the rear fuel pump, and just turned the key till the pistons landed where they were supposed to, like roulette. Everything turned out fine after the walnut blasting.

2010A8Lsport

I do a lot of stainless steel fabrication for my job so I just made up a square block with a hex head on one end to fit in between the Allen head bolts on the main crank pulley. It was very easy to turn with a gear wrench on it and the spark plugs removed.