There is no recall on this item, but the wiring harness is surely bad, and if it isn't, it will. On your engine, and that in the 93-95 E320, the wiring harnesses go bad. The insulation on the wiring degrades, and the wires short out.
You're going to have to have it replaced. I believe they cost about $550 for the harness, and a couple hours of labor to install. Figure about $800.
Many MB dealers are replacing them on a "goodwill" basis. They have no obligation to do it, but if you bought the car from them, or have taken it in for service there, they may be more inclined to do it.
In many cases, they'll provide the part for free, but you'll have to pay for the labor.
This engine wiring harness problem from 93-95 has been discussed very frequently on this site, and the archives are full of good information.
Try the search function under "wiring harness", and you'll spend more time reading these posts than sleeping.
Also, it's not the 3 coil wires that usually go bad, nor the 3 spark plug wires, but the ends or "boots" of the wires. Your tech might be changing the wires unnecessarily.
2001 E430, Bourdeaux Red, Oyster interior.
1973 280SE 4.5, 170,000 miles. 568 Signal Red, Black MB Tex. "The Red Baron".