Power problems on Amtrak’s Northeast Corridor continue to cause headaches for rail travelers despite millions spent to upgrade aging equipment.

Three incidents this week caused significant delays between Philadelphia and New York.

Amtrak said service was disrupted Thursday morning and afternoon because a computer problem prevented enough power from reaching trains.

Trains also sat idle for several hours Tuesday because of a transformer fire in New Jersey.

There have been seven disruptions caused by problems in New Jersey since March.