Car can not drive faster

[GORAX]

Hi togehter,

My car starts normally. When I drive off and shift up the gears, my car tries to shift down and slows down. This happens in 4th and 5th gear at around 100 km/h. It's as if it's stalling itself. Could the gearbox be broken? It shifts up normally. It showed STOP because the engine is overheating. No error message about the clutch or gearbox.
The engine also gets louder because it tries to shift up. I always have to help manually.
VF7**************[VIN obfuscated, can be read by forum staff]

Citroen c4 grand picasso 2015 diesel automatic.

[GORAX]

PROBLEM SOLVED

[moizeau]

Please tell

[GORAX]

Das Problem wurde falsch diagnostiziert. Kühlwasser Kreislauf war verstopft.


The problem was misdiagnosed. Cooling water circuit was clogged.