Kenmore 30" sealed gas cooktop Model # 911 32355 burners will not burn low

SOURCE: Thermador Gas Cooktop Won't Stop Clicking : SGC304RS

theres a part in the cooktop called a spark modual. replace it. when i goes bad the problem your having is what it causes

SOURCE: low flame from gas cooktop

you can adjust the flames as follows pull a knob and look in the end of the brass peice you will see a small screw first you have to find a screw driver that will fit then with a pair of pliers hold the outer peice with the burner on and turn the screw one way rasies other lowers ideal adj is to turn buner all the way up then fast down if flame goes out to low keep working like that till flame is low but doesnt go out

SOURCE: Thermador 30" gas cooktop SGCS304RB

Do you hear gas? If so, take a needle and put it through each one of the small holes where the gas comes out.... Also look for a little "white-dust" where the sparker makes the spark. (located probaly at back of burner). If there is a white dust build-up scrape it off with something (needle) and give her another go...

SOURCE: Clogged burner on gas cooktop

lowly is it the left burners that won't lite? I only ask as depending on the model some of the Thermador cook tops had simmer control burners. This is a 3 part system on the burners. 1 a simmer control, 2 electric solenoid, 3 potentiors. When you turn on the burner the potentior tells the simmer control to send power to the gas solenoid. At the same time the unit will spark. If your unit has extra low on the left 2 burners then you have this system. The usual problem in the potentior. Hope this helps.

SOURCE: Gas Burner ignitor is not working

Yes it should be an easy fix.
Ignitors simply go bad from time to time.

If you have a meter you can check to see if you have voltage going to the ignitor. If you do, and it isnt trying to ignite, replace the ignitor.
If you have no meter, ignitors are usually less than 30 bucks so you will not be to much in the hole by just replacing it.

If you lift the cover to access the ignitor, it should be held in by two crews, the gas tube, and a wire to the flame sensor.

Make sure you turn off all gas and electric before disassembling.

You can find ignitors at your local appliance parts supply house.
All you need is the model and serial numbers.