1998 S70 Volvo stalling when stopping intermittently.

Hello, it's not terribly complicated. When the stalling occurs, something essential for engine operation is missing. Fuel delivery, ignition spark, air to the intake manifold. You could have some kind of electrical failure as well, but that's less likely. Testing will be needed when the problem occurs; perhaps that's why your "European Car Mechanic" hasn't gotten it yet? Use this link to find some shops near you that can help with your concern: www.repairpal.com/repair-shops