I was gonna suggest the PCV and suction jet pump, but it looks like you're on top of it. Refreshing to see some members that do actual searching and due dilligence.

P.S. Just for clarification when your reading data logs (block 32) on the vag com, when you see a -% number it means the ECM is taking away fuel, meaning its running rich. If you see a +% its adding fuel to compensate for extra air in the system, meaning it was running lean. Hope this clears that up for ya.

 

Lol yea. After reading a majority of the posts on this forum and others it seems to me that most people with audis aren't very car smart or tool savvy. I've worked on cars all my life.

But with regards to the too rich too lean. I have a standard obd2 scanner and it reads sensors too. I just look at codes and pending codes and its what is tellin me lean system. But after replacing the pvc valve with one from the dealer. The car stills runs fine but idles high. But when its blocked off completely no problems at all. Sooo eliminating the unnecessary emissions crap will be taking place shortly. Germans make some great stuff but this vac system just puzzles me.....

 

The vac systems on these cars are actually pretty simple, this stupid 89 4runner in my garage that im doing a set of head gaskets on is a nightmare in comparison.
Anyways, did the engine still idle high after you cleared all the codes? The engine needs about an hour of driving time to re-adapt after the repair.

 

i will say i just had this problem with my 03 1.8t. i didnt think to much of it until my coilpacks went bad, and i got the same error codes as you. So i grabbed the Hitachi (read the audi brand blow) and new ngk plugs and that solved my rough idle problem at the same time. maybe this helps?

 

still idles high at random times. goes from 800 to 1200 to 900 to 1000. whatever it wants. still running lean. when i plug the crank vent cam off completely runs just fine. soooo i'm assuming there still a small leak in there somewhere. either that or the dealership gave me the wrong valve.

 

Have you looked at the suction jet pump and the three vacuum check valves? The valves look like a little saucer with a black and grey side on them. They tend to rub on things and wear a hole in them. It can be as small as a pinhole, or as large as your fingernail.
You definately have a leak somewhere.

 

Yea, all of those will indeed be taken care of in due time, by eliminating all unnecessary vacuum hoses.

In other news. I'm actually kinda disappointed in myself in that I didn't catch the cam tensioner gasket when I did the valve cover gasket. Because it is indeed leaking. Nothing like the nice smell of Royal purple dripping out onto the exhaust. mmmmm mmmm Ordered me up a new gasket to go there along with the tool to take tension off the chain.

I bet your liking that Sierra pickup truck with gas prices shooting up like they are.

 

I get between 16-19 mpg with a 5.3L V8, its not so bad. I've spent a total of $700 keeping it running in the last 4 years, so its give and take

 

That and it probably runs on 87 octane, saving you $0.20/gallon vs the 91 octane we all have to run in our Audis. $3.69/gallon for 91 & 92 octane around here, and it's not even summer yet. Wouldn't be surprised to see it get over $4/gallon soon. Man, the middle east really needs to calm down.

 

dude i hear u there. The gas has been jumping up like crazy lately. i pumped up on saturday for 3.02 and today it went up to 3.28 argggh someone needs to regulate this crap.