Ok, this is not good at all. I just encountered this problem on my way to Hardees. I started up the car and thought nothing of anything but quickly noticed that as I put it in gear (automatic) that something was very wrong. So when the check engine light came on and started blinking some colorful words came shooting out of my mouth. Then it turned to a solid check engine light but not for long (2 minutes maybe). Then the blinking came back on for about a block and then the solid came back on and now nothing...The nothing is not at all nothing. So I took the car home immediately and opened up the hood to see if it was low oil or something like that but no. I see this white smoke (very light) coming from the back of the engine after a few second no more smoke.

So then I start the other problem shooting. I turn the car back on(No smoke at all during testing) in park, reverse, and neutral. Everything sounded right and rev'd up right without problem. When I switch into any of the drive features 2 through D all hell breaks loose. It sounds like my car is going to explode. You know what the old muscle car sound is when it is almost choking itself, well that is it but not because of power. The RPMs are dropping from normal to about 200 very quickly multiple times and keeps doing it as long as I am in those gears.

What do you guys think?

No CEL anymore and I can leave it in drive without one coming on but something is very wrong. Is my EGR valve stuck, tranny screwed or something worse?

FYI: 1997 A4 2.8L 12Valve Automatic FWD