J'ai lu ça(texte ci-dessous) également sur un forum autre...qui tend à dire que le PDT 999 est bon. Par ailleurs, je viens de voir que Claude alias Gédéon dit lui que c'est ce qui se rapproche le plus de la KTS 301...
the PDT999 is good. But for a lot less money, just get the tool sold by Tore at Bergvill F/X and use it in conjunction with the free scantool software developed by Ricardo over on Rennlist.
T-OBD - Diagnostics For Porsche 968, 964 and 993 - OBD Diagnostics - Products
In addition the 19 pin connector Tore sells is $8.31 on newegg.com You will need this for a 964.
19 Pin OBD OBD2 968 993 944 964 Adapter Lead Cable Diagnostic Tool For Porsche - Newegg.com
And the scantool link:
http://www.bergvillfx.com/files/T_OBD_Software.zip
You will need a laptop or a windows pc with a long USB cable.