I have a 1999 300 Turbo Diesel. 185,000 miles. great Car, except it sputters and stalls on freeway. It is worse on hot days , better on cool humid days at the coast. I pull over to side, wait a few minutes , start for 30 seconds, and away I go. Two separate MB garages, cant figure it out. Replaced fuel pump, filters, fuel, nothing works.
Anyone else with this problem?

please advise
Abe U

 

Since your car is a diesel, either the engine isn't getting enough air or fuel. But you said that they changed the fuel pump, and filters. Did you take the car to private shops or dealerships? Did they replace the injectors too? If all that's been done, I can only think that something's wrong with the electronic fuel injection. Usually cars run better when the weather is warm rahter than when its cold, so your situation is abit unfamiliar to me.