IMD

I'm very pleased to hear that. I hope that this post will help others too.

roylok

Update on n208 valve. The valve eventually failed completely, and the culprit was a piece of screen mesh jamming the valve also affecting the oil flow. Now I'm thinking about doing an oil change to make sure that there is no other pieces floating in the oil.

TGR172

http://www.autoserviceprofessional.c...i-cam-position

Audibb

Roylok, I just experienced the P0021 and got my 07 A6 4.2 into the shop. They just called and said that a piece of screen was blocking the cam solenoid. They removed the piece of screen and the car is running well again. Do you know where the mesh screening came from that was blocking your valve?

roylok

My understanding is that the screen sit at the bottom of the valve to stop particles from getting in the valve. Over time the mesh disintegrates gets in the valve and blocks the valve movement and/or oil flow. In my case it happened after driving the car hard, redlining the engine. The revised version of the valve (p I believe) does not have the screen mesh. The second solenoid failed on me shortly after , same issue so I had all four replaced. I would strongly recommend replacing them as preventive maintenance. It happen to one, the weakest will go first of course, the others will follow shortly. But it could be worse, at least it doesn't have the timing belt issues or chain guides other engines have.

Audibb

Thanks! I did not take it to a dealership, and the shop I took it to was stumped on where the screen could have come from. Now I have an answer!

Audibb

Sorry for one last question - what is the cost of replacing 1 or all four?

roylok

FOr $60-$80 a piece at my local Audi dealer. You can even get it from WV dealer if you give them the part number. WV dealer quoted me $175 for one, I don't know why more expensive at WV, maybe the guy at the counter was just a *****, or maybe because Audi dealer gave me a break.

Part number: 06E109257P

Audibb

Thanks!!!!!!

TGR172

Hey guys. I had the same problem a while back with almost the same exact symptoms. The vagcom can help out identifying the exact actuating valve. Can't think of the exact part of the software to test them with as I don't have it in front of me but its the routine that activates all the engine selenoids etc. You can activate each one manually or automatically. Use the manual mode. For those actuating valves open the hood and get in a quiet place and activate each individually you can hear the click for each vagcom doesent give an error report unless the selenoid on the valve is shorted ... Which usually isn't the case. You can ohm them out till the cows come home and they most likely will read fine because the selenoids are electrically fine. The valve itself is usually stuck so if you don't hear a click then thats the one that is stuck. I then pulled it out and connected it to a power source and could feel the selonoid trying to move the valve. Those valves control the oil flow that pressurizes the automatic timing ,advance /retard of the camshafts. You can pretty much tell which bank/side of the engine the bad actor is on by which cyls are misfiring. Ok that said, yes sometimes the screens, which were covering the ports on the side of the valves get worn and get stuck in the valves and jam them. Now if you have money to spare go ahead and buy a new one. But, there is a simple way to clear out the jam in about 10 min once you have it removed from the engine. Did it on mine about 50k miles ago and no problem since. I posted a procedure on the vagcom forum a while ago but I'll give a quick overview here. Get some mmo to lube and clean the valve. A small nail/tack with a head on it, and a vice grip or pliers to hold the nail about half inch from the head. Put mmo in the ports to lube everything up. The valves are spring loaded so put the head of the nail into the round hole on the end/bottom of the valve and hook the head of the nail on the inside of the hole. Use that to pull the plunger of the valve out. Might take some effort, then push it back in. Keep exercising it like this several times until the spring in the valve allows it to smoothly retract on its own. This frees it up then hook the power source and check that it is operating smoothly. By hooking the hole at the bottom you are not damaging any of the ports or o rings. Reinstall and ur good to go. Look I know its an Audi and you're thinking omg I can't do that but they are not rocket science and are not unique to bag. Jap and american cars have pretty much the same setup on the newer ones. I wouldn't worry about the screens damaging the oil system it would have been damaged already by now.