Switching to ICE during acceleration

Ever since I brought my Volt into the dealership for the most recent recall my car has been abruptly switching to ICE during hard acceleration. I?ll try to start off slow from a red light but when it gets to about 60kw it randomly shuts off switches to the gas motor and creeps along at 20mph until it figures out that it has a full battery again. This process takes about 20 seconds and can be quite dangerous. The check engine light has not come on.