So I did some digging, because now I am thinking I should purchase a backup to add to my spare parts heap.
Here is a website showing the interchangeable throttle bodies for the B7 RS4.
http://www.kakapart.com/parts/audi-079133062b.html
I entered the RS4 throttle body part number 079 133 062 B which produced the below list. The Dorman throttle body I posted a link to on Amazon (part 977-820) shows that it is compatible with OEM part numbers 67-3003, S20002, 12570790, and 19420034. As you can see, both Opel and Chevrolet use part number 12570790, so the Dorman throttle body is compatible with the B7 RS4.
AUDI 079133062b
CHEVROLET 12570790
PIERBURG 7.14423.07.0
VW 079133062B
PIERBURG 7.14423.00
OPEL 12570790
OPEL 25312095
As an additional bit of confirmation, in the thread below a person confirms that the Cordone throttle body (part 67-3003) works perfectly in his B7 RS4. The Cordone part number is listed in the compatible part numbers for the Dorman 977-820.
Testimony from link below:
I ended up with a Cardone remanufactured unit. Turns out the throttle bodies are indeed the same. They are manufactured in Germany by a company called Pierburg. If you go to Rockauto.com and search for 67-3003, you should be able to find it for about $220.
If you do go the Z06 route (which I cannot vouch for, but should theoretically work), be sure to get one with the silver throttle blade. They made a revision for MY09 (I think) where they changed the throttle blade to a bronze color, and the blade also opens in the opposite direction.
The Cardone unit is working fine on my car, and the shop that installed it tested it on another RS4 before installing it on mine.
I don't know how the part will be in terms of quality, reliability, but so far (fingers crossed) at $220 versus $1200-1400, I'm willing to go the cheaper route. Hope this helps anyone having throttle body issues!
https://www.audiworld.com/forums/rs4...2715906/page2/
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