I just found out that the WETT chip costs aprox $1200 here in Mexico,and since the A4 chip costs half that in the US, will a chip for the A4 bought in the US work in a A3? Would i have to take the car to the US or can they send the chip?
Any info appreciated.

Not sure if an A4 chip would work in an A3. But it is something I have thought about also.

But, I believe TAP can do a chip for the A3 1.8T. I mailed them about it some time ago. You can send them your ECU, they fit the chip (not socketed), and then they send the ECU back to you in a couple of days. That's what they told me.

I would think WETT provide a similar service.

Alan.

It's not a question of physically similar chip but the software in it. There are lot's of different ECU:s both in A4 and A3.

The numbers on the cover of the ECU is the way to make sure there is a suitable software available. If there isn't, then the chip manufacturer will make you one by reading your software and tuning it.

Euro and US softwares are diffent.

Marko Litmanen
A3 1.8T Wett 1.0 K&N

try neuspeed they tell me they are tooling up for the A3 and have 3 items of software currently available specifically