a6 ecu in a s4?

Reply Subscribe

Thread Tools

Search this Thread

01-20-2006, 08:21 PM

ml-drs

AudiWorld Member

Thread Starter

Join Date: Feb 2005

Posts: 325

Likes: 3

Received 1 Like on 1 Post

a6 ecu in a s4?

I have a 2002 s4 tip can I use an a6 ecu? the a6 box number is 4B0907551AA and a 2002 s4 tip box is 8D0907551AA as per the GIAC web site info. Has anyone tried to do this?

Reply Like

01-20-2006, 08:47 PM

Nigel (no more S4)

AudiWorld Super User

Join Date: Jul 2004

Posts: 4,837

Likes: 0

Received 0 Likes on 0 Posts

won't work

Reply Like

01-21-2006, 08:17 AM

VandyS4

AudiWorld Super User

Join Date: Dec 2003

Posts: 6,906

Likes: 0

Received 0 Likes on 0 Posts

What's more important is the box letter (A, H, T, M, J, etc.).

I'm pretty sure that if the box letters are the same, you're good to go.

Reply Like

01-21-2006, 11:47 AM

Nigel (no more S4)

AudiWorld Super User

Join Date: Jul 2004

Posts: 4,837

Likes: 0

Received 0 Likes on 0 Posts

nope. read the s4 guide, it states that the a6 code is different to the s4 and can't be used

Reply Like

01-21-2006, 02:29 PM

ml-drs

AudiWorld Member

Thread Starter

Join Date: Feb 2005

Posts: 325

Likes: 3

Received 1 Like on 1 Post

they are both AA boxes- still a no go?

Which guide discusses ecu compatibility? Do you have a link to it?

Reply Like

01-21-2006, 06:53 PM

Nigel (no more S4)

AudiWorld Super User

Join Date: Jul 2004

Posts: 4,837

Likes: 0

Received 0 Likes on 0 Posts

there's an S4 and RS4 self study guide. I don't have links but you'll find them at

S4 guide is in mjtaylors sig (i think)

and the rs4 guide is on modifieda4's page.

It states in the s4 guide

"A tuning protective device prevents the S4 engine control unit being installed in the A6"

I know that's the opposite way to what you're looking, but you gotta think, if it doesn't work one way, why would they make it work the other....

Reply Like