jahnetik

So my problem is a heavy vibration in the car only when I'm idling in drive. RPM's don't seem to dip and I can feel it mostly in the steering wheel and seat. Check light is on.

Symptoms/Details:

- Vibration felt all over car when idling in drive. Stops in neutral

- Audi ran codes, said my Vacuum check valve was failing. Replaced it myself. Didn't fix anything

- Audi said they got a second code for the secondary air systems and would need to run codes again to see what came up after replacing the check valve

- Gas mileage has gone down.

- Power is somewhat lagging.

- New air filter and recent oil change

- Intake isn't clogged

Anything would help guys!

Thanks
Jason

jahnetik

Nobody? It's starting to get worse

cjf337

My wife's 2007 A4 avant 2.0T has the same problem - idle is rough when stopped at lights in drive, but if you move to neutral, shaking seems to stop. Car drives fine otherwise and mileage is normal. I looked this up on the Internet when we bought the car. Seems to be a "normal condition" for this engine type. I did take it in once and they replaced the vacuum valve. Maybe got a little better but it still runs a bit rough in idle. Drives great otherwise.

The only other thing I've noticed is that we are going through about a liter of oil every 3000km. We bought used in 2010 and the car didn't need additional oil for one full service cycle (about 10 months). Then about 3 months after the first service, 3400km the oil light came on. Needed a lite of oil, and it's been like that since - every 3000kms or so need a liter. Dealer says its not unusual for audis to need oil that frequently, but there is no oil leak and my 2008 A6 which I had for 3 glorious years never needed a drop added between service dates.

Not sure I helped you, but suffice to say, it's annoying when the A4 shakes, but it's a great car otherwise.

jahnetik

I just checked my oil and it's low, wtf. I'm not supposed to change it for another 2k. Anyway, I'm going to change it today but I'm guessing that won't resolve my situation. But thx man

Jason

seanf

sounds like a bad motor mount, previous non audi cars of mine had problems vibrating in drive and it was usually a bad motor mount

jahnetik

I've had the motor mounts checked and it wasn't them. I'm leaning towards a possible misfire even though it didn't come up on the scan. Car feels sluggish

seanf

well I have an ebay vag com cable and can data log for you if needed, do you have the 1.8t or 2.8?

jahnetik

I have the 1.8t Quattro

seanf

could be the pcv valve or suction jet pump, when either of those go the car runs like crap