from wat i know (not much) they bypass ur ignition in a way so that when u remove the key ur engines for a preset time , i saw one being fitted to a fucus RS , the timer (HKS) had only positive , negative , handbrake earth and an ignition connection , dunno how this would work with the vag immobiliser centrsal locking tho
andy do u have the oil temp guage , wat i do is to let my engine sit for about 30 secs b4 shutdown as long as the temp is below 90 , (running temp) if it is above this i wait tilll it is below this , the last 5 minutes of every journey is took at low beans, helps drop temps