belikerob

Hello Audiworld, For the past year I have had a problem with my 2007 A4 2.0t When I accelerate quickly or up a hill my car makes a horrible sound, it sounds like a metal piece repeatedly and very quickly trying to move but hitting another metal piece that is blocking its path. Simultaneously a huge plume of white smoke comes out the exhaust (NOT sweet, it smells like burnt oil and a hint of rotten eggs), and then a loss of power which lasts until I give the car a solid 5 seconds of no acceleration/foot on gas. If I fight it and try to maintain speed it starts to buck (jumps forward for a split second then drops speed for a split second then jumps forward, repeatedly at a fast rate), then smokes even more, then finally COMPLETE loss of power. (car couldn't turn back on, had to be towed to shop both times)
Tests/details:
*2007 a4 2.0T 75,xxx miles
*passed compression test
*Turbo has been literally red hot on 2 occasions after particularly bad uphill highway incidents
*had to replace the spark clubs after one particularly bad uphill smoke incident
*car over consumes oil (sorry cant give an exact amount)
*car occasionally makes a soft thump noise (realized this is usually when im a little low in oil)

*replaced the pv valve and 2 other pieces that were recalled
Not sure if I forgot anything, but ill update if I did.

Does anyone have any idea what is causing this problem?

Shanster

First thing to try is changing your air filter. I've heard that this is a remedy for your symptoms. (http://www.jhdiesel.com/failurechart.htm) It is a relatively inexpensive part at Autozone. You clean out your airbox while you are at it. It is probably full of leaves, etc.

Second, there could be some play in the compressor shaft of the turbo.

Thirdly, leaky injector?

Fourthly (?), I've read that when you're at wide-open-throttle (WOT) the fuel mapping runs in an "open loop" meaning fuel sensors are ignored and a preset amount of fuel is injected, causing the engine to run rich. Which is normal, but doesn't explain your lack of power and the noise.

Also, there have been 3 big recalls/warranty extensions over the years:
1.)coil packs (recall)
2.)intake cam shaft, cam follower, high pressure fuel pump (warranty extension) if you haven't thrown a code, you'll need pay upfront to have your cam follower checked to see if it is completely worn through.
3.) PCV (positive crankcase ventilation) valve

Have you tried searching the forum for posts that include your symptoms? It only takes a few moments and should be the first thing you do.

Supatek

You need to check your low side fuel pressure and volume as well as do module duty cycle

audi2007a4

I have Audi 2007 A4 and exact same issue, but can't seem to figure it out.
I did have following three recalls done but issue still remains
"belikerob" were you able to find out what was causing this?
Please let me know

Thanks


RECALLS DONE ON my AUDI
1.)coil packs (recall)
2.)intake cam shaft, cam follower, high pressure fuel pump (warranty extension) if you haven't thrown a code, you'll need pay upfront to have your cam follower checked to see if it is completely worn through.
3.) PCV (positive crankcase ventilation) valve

MikekiM@PureMS

You're going to have to get ahold of a VAG-com and scan the ECU to see what codes are showing up.
I'd double check to make sure you don't have a clogged catalyst first. But without having any details with what the ECu is showing, it's like throwing darts in the dark.

sswss

I have 2006 audi A4 and exact same issue. I had mass air flow sensor replaced. the problem is solved. Parts number is 06F 906 461A Hitachi brand. $127.50 It took me 15 min to replace it.

sswss

I have 2006 audi A4 and exact same issue. I had mass air flow sensor replaced. the problem is solved. Parts number is 06F 906 461A Hitachi brand. $127.50 It took me 15 min to replace it.

sswss

Sorry! I was wrong, After having Mass air flow replaced, the problem still exiting.

Shanster

Agreed. This should always be step one.

Shanster

belikerob,

Any updates? If your problem was solved don't forget to update your thread!!!