Strange gearbox behaviour

[Gzzsbj]

morning learned friends, I’ve got a 2010 c250 cdi with the 7g Tronic. box. most of the time the box works fine, but recently it’s taken misbehaving. From cold, and as long as you keep driving, it’s performs faultlessly, but if you interrupt the journey by stopping the engine, on restart it goes into a mode best described as somewhere between “E” and “S” modes. Gear changes are delayed Even though it’s in “E” and the engine note is loud and rough sounding, also, worryingly it will not change up into 7th. nothing I do will make it go into seventh. turn it off and on again all returns to normal.
Its done 91,500, had a gearbox service in 2016, and booked for another .in two weeks. fuel consumption is approaching 60 mpg on a run. anyone got any ideas?? !

 

[W1ghty]

I would think a fault code would be logged , get them to check before they do the gearbox service .

 

[slade1]

Electro plate? get the codes read using MB STAR diagnostics before throwing money at it.

 

[alexanderfoti]

Sounds like its going into limp mode ( Can happen even with no engine light) and the box is reacting to that. Next time it happens, see if it will rev past 3500rpm.

 

[Gzzsbj]

/ /'''

Sounds like its going into limp mode ( Can happen even with no engine light) and the box is reacting to that. Next time it happens, see if it will rev past 3500rpm.

had the car into an auto transmission specialist in Swansea yesterday (Mike Tucker) mainly for an oil and filter change, and he read the stored codes while it was there. There were two:
P047128 exhaust back pressure sensor 1 has a malfunction.
P245396 the input for differential pressure sensor 1 in the dpf has a malfunction
Mike reckoned the dpf was clogged although the eml light isn’t on and the car drives better than ever after the gearbox service. Anyone got any further ideas?

 

[alexanderfoti]

/ /'''

had the car into an auto transmission specialist in Swansea yesterday (Mike Tucker) mainly for an oil and filter change, and he read the stored codes while it was there. There were two:
P047128 exhaust back pressure sensor 1 has a malfunction.
P245396 the input for differential pressure sensor 1 in the dpf has a malfunction
Mike reckoned the dpf was clogged although the eml light isn’t on and the car drives better than ever after the gearbox service. Anyone got any further ideas?

Wiring fault
Differential pressure sensor fault
hoses to DPS sensor blocked/clogged
Exhaust backpressure sensor is probably faulty or blocked.

DPF will not regen with codes stored and will block up again.

 

[Benzowner]

and the car drives better than ever after the gearbox service. Anyone got any further ideas?

Insufficient fluid or knackered fluid in the gearbox.