Hello , thanks for your question in the autoaid Community.
Your described fault Code means: P008792 the fuel pressure in the system is too low. The function or the statement is incorrect.
Look in the is values for low pressure and high fuel pressure.
In this part you have to look where the fault comes from.
The System have a high pressure fuel Pump at the Engine, sometimes there is any fault and this type must be replaced.
But it could comes from the lower pressure fuel pump in the tank, then you have to look for the fuel filter and for any leaky hoses.
Did you have guarantee on this car? Then bring it to a Daimler dealer and let him check this.
Because there could comes fast very high costs if there is a fault.

Greetings
Team autoaid