Moin moin ! first of all I have to introduce myself ! I am now proud owner of a PHAETON 4.2 with lpg ! since I on google at problem time again on the sides of motortalk and unfortunately no advice find I decided to describe my problem with the fat to get advice from you ! The error nr. 1 before some weeks went the mkl! I went into the workshop ! the error secondary air too low on bench 1 and 2 ! errors deleted continued ! 3 days later date in the workshop pump runs but mkl again ! another 1 week later again in the workshop this time the mechanic with pressure air blown off and the pump to establish whether what and is wrong ! to test whether the pump runs we have the temperature sensor off and when switched on the ignition the pump runs like normal ! after that the mechanic with pressure air is blown in the pipes to determine whether or not to give again the error is installed !