The valves of each cylinder of the car engine are remained closed by using a pair of arms that change the conventional engine’s roller-type rocker arm. The car engine P2811 code is one of these arms what follows the cam profile while the 2nd arm joins to the valves. During the normal car engine process the two arms are united by a locking pin. The car engine P2811 code seems a kind of powertrain problem and this problem is not very difficult to solve. You can fix this problem at cheap rate. The car manufacturer of Specific codes, which have a ‘1’ as their 2nd digit to specify they are unique to a specific car make or model.