Jeff had decided to commit suicide by carbon monoxide poisoning while Zach and Lynne were at Zach's hockey game, but they returned shortly after they left because Zach had left something behind. Lynne discovered Jeff in the garage with the engine running and called 911.
After Jeff was admitted, he tried to attempt suicide again. Zach assisted in one attempt by faking a seizure to distract the hospital staff so his father could grab some lethal drugs. However, House saw right through the deception and stopped the attempt. Zach begged House to let his father die.