As far as naming goes it really depends on what book you are reading. I have a couple from Bosch one has CIS as Continuous Injection System and the other has it as Idle Speed. My Bentley for VW has it as Injection, for Porsche has it as idle, but the best is the fuel injection only book that has both. > Your misidentification is actually quite common: > > CI -- "Continuous Injection" > CIS -- "Constant Idle Speed" > > These are Bosch's terms, adopted by Peugot, Renault, and Volvo. Andrei