C4 Grand Picasso Exclusive year 2011 82kW 112Ps AGR

Hi, does this AGR have to change the valve, where exactly is this one? Left behind the engine or right behind the engine? Have/had a jerking when starting up (EGS6), changed the battery (but was from 2016 original Citroen) and Luffilter, make me think that the Egs already switched better, but when starting up or 1 and 2 gears the power is somehow delayed, after that it goes without problems. These 2 things are exchanged for the reason because in the tester: Battery weak and AG When replacing the battery, I noticed at the top of the fuses that there is a 5A fuse missing!