Hmmm, well if an autoparts store around you has them for cheap then I'd say go for it! And sometimes you can trust ebay and sometimes you can't. $80 is a good price, as long as its brand new. I got mine from this site:

http://www.aboveallmotorwerks.com/Pr...0905351_S.aspx

Its a bit more than ebay, but it worked great. I'm not sure if thats the exact item you need, but the number is 4A0-905-351 A/47 or something like that.

Its up to you really, I know local places around me wanted $220+ for a new one.

Hopefully it fixes your car!

 

I went to that site and looked up 2000 audi s4 ignition control unti, same thing?
http://www.aboveallmotorwerks.com/BV...ERU_4A0905351A

Ebay was a used ICM