The check engine lamp for the up-shift delay could be related to trans repair, as there is a vacuum line the connects to the control pressure cable & that is what the check engine code means.
Any car that the transmission STARTS off in first gear can roll back on a hill, and the E420 does start in 1st gear.
Cleaning the throttle housing & butterfly will help keep the engine from dying while under strain at low speeds.
MERCEDES Benz Master Guild Technician (6 TIMES)
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190E 2.3 16V ITS SCCA race car (sold)
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