Siemens EQ7 series no coffee but a lot of steam

Hello and good day,

Have here a KVA from Neff, which according to my research should be identical in construction to the Siemens EQ7 series.

Error: Very little to no coffee, pulp mushy, sometimes remained dry. Now and then, however, normal function.

Procedure in case of error:

1. grinder grinds2
. Brew group presses3
. Simmering sounds begin, light steam escapes around the brew group4
. Motor from ceramic valve can be heard, at the same time pump starts pumping. Steam immediately gone, it is now dripping at the brew group while the pump continues pumping5
. Pump pauses briefly and continues pumping6
. Shortly thereafter, the motor from the ceramic valve is heard again, after which steam escapes again and it continues to drip7
. Brew group moves, there is then a very loud short steam escape8
. Brew group throws out marc.

I first cleaned the brew group (upper strainer and crema valve), replaced the upper thick piston seal and the small seal on the inlet spout. Checked outlet for continuity, was fine.

Pomace remained mushy, then researched that this should be normal.

Would now make out the ceramic valve as the cause of error, but wanted to exclude other causes of error first, because you often read that errors have remained after replacing the ceramic valve.

Maybe someone can help me or describe the normal operation of the machine.

Sincerely, Jürgen