1994 Mercedes c220's transmission.
 

Dear friends:

My 1994 Mercedes c220 has a strange problem with its automatic transmission. Whenever the car is started (either cold or hot) and driven, the transmission seems to get stuck at gear 1 or 2
unless I try to increase its RPM to about 2800. Once the RPM reaches 2800, the transmission shifts perfectly well at all gears afterwards. It that a normal behavior for Mercedes 722.4 transmission?

Does my car's automatic transmission has some modulator that can be tweaked to improve shifting behavior?

Thank you very much for your help.

Best regards,

Eric

This is normal behaviour, but only when the car is cold started. Sounds like this feature is malfunctioning.

It is called "up-shift delay" and is a feature to help warm up the
cats during the start enrichment. When your car is cold it should
wind the gears out for a minute or two. when the car is warm
to kinda warm, it should delay shifting for around 30-45 seconds.
This keeps the revs up to warm up the emissions equipment faster. Normal condition.
DR.D

Thanks a lot Blackmercedes and DR.DIESEL for your helpful replies. DR. DIESEL's description is exactly as my car's behavior.

Best regards,

Eric