I have a question about a MH can light where I work. They put a new lamp in it awhile ago, but said that it needed a ballast. Is the ignitor still pulsing even although the ballast is dead? My question is because this bulb had recently started turning a grayish color, and I figured it was due to the ignitor pulsing at it. Not sure though.

Whats the wattage? How do they know it needs a ballast. I know in all the instances where I run into a bad ballast the ignitor is not running due to the fact the starter is in line with the lamp. Once the lamp is lit the starter turns off so if the lamp is lit it shouldnt be pulsing. If the ballast is dead then it shouldnt be working either as far as I know. Im not saying it cant, Im just saying from my expirence. Hope that helps!

There might be loose connection to the lamp - it carry only those high voltage pulses, where the air break-down. I had a lamp defective in the socket (Rx7s lost it's cement bound, so the contact disc bend and didn't reach the socket), the lamp only lightly flickered, but the arctube was gray after one hour.