My car is working perfect 9 months a year, but when outdoor temperature is +20 C or more, it easely goes into limp mode in stop and go situations. Sometimes after being parked for more than an hour, and the only cure is to open the hood and ventilate for five minutes and it works again!
There is no indication on the MB garage test tools, I have been there several times. One time I got there limping without turning ignition off, but as soon as they open the hood and connect the computer, everything is back to normal. When I leave, it starts to limp at the gate...
Limping in my case is the same feeling as when the speed limit comes on at 250 Km/h, but this reduces the revs to 1500, which is max 30 km/h on 2:nd gear.
I have not started to change pieces since I have no idea where to start, and the garage refuses to check the car with the hood closed, so they will never be able to detect the problem!
The car is a 94/06 and I have had this problem from about 20.000kms and now it is at 50.000km, pretty low mileage and well serviced all the way.
Anyone with similar problems and possible solutions are most welcome to reply. IŽll follow up on your ideas, so we all know for the future...