My mother-in-law's pearl cooker had three of the hobs not working...
If you take off the circular plate and the burner ring that's underneath the plate you will be able to see the tiny hole in the gas jet (it's about a couple of inches below) - you may need a torch to see it clearly. You should then be able to unblock the jet by poking an unfolded paper clip into the hole. It worked for us so fingers crossed it may work for you.
Alan Elliott, October 2007
