300 E fault that the Serv. Officer does not resolve

Hello. I have an older Mercedes-Benz 300 E, a 1998 model, that runs perfectly. It starts right up and sounds like new. It really does run very well, but it has a problem that even the official service center hasn't been able to fix. The problem is that the engine stalls unexpectedly. After 30 to 60 seconds, you turn the key and it starts again without any issues. This happens both when the engine is cold and warm; sometimes two days go by without it happening, or it can happen twice on a short 10-kilometer trip. I've taken it to two official Mercedes service centers. At one, they kept it for 15 days and couldn't find anything wrong, saying it wasn't faulty on their end. It stalled again as soon as I got back from the shop. I took it to another official service center, and it was the same story. It keeps stalling whenever it wants. What could be wrong with it? I'm afraid to overtake; it might stall at that moment! Thanks

Did they change the phase sensor?

I'm not sure if this model has a phase sensor. If you can send me the chassis number and engine type,
I'll study the system and give you a more accurate answer. But if you do a test, we'll know for sure. First, when it stops, check if the fuel pumps are priming, since it has two. If they aren't, try bridging the relay between terminals 87 and 30. I hope this helps.
Greetings from Tenerife.

Look that the injection relay does not have false welds that when reheating produce lucky cuts and keep me informed.