I am currently repairing a Thermador Cooktop model # SGCS304RSI. Originally the problem was that I had one XLO burner (top right) not receiving gas and the other XLO burner (lower right) was being a little bit tricky about catching a flame yet would eventually light and all 4 ignition heads were sparking fine. Based on Gene's advice I replaced the pots and simmer control (using kit) and both XLO burners started working perfectly, it was awesome!

As I stood there in bliss watching everything work wonderfully feeling the pride of my DIY moment and thanking all you guys for your support, I had the lower right XLO control in simmer mode. I had never known this is what the XLO simmer mode is supposed to do! So I started replacing my grills and when the left grill touched the frame the active lower right XLO burner flame went out and it stopped working correctly! The igniter head still clicks but no gas! So basically now I have just the opposite as when I started. The top right XLO burner works perfectly but the lower right XLO doesn't have any gas feeding to the burner. I just can't hear any gas getting to it at all.

Do I need to replace the pot again on that XLO controller and if so what happened? Could this now be an issue with the valve cylinoid?

Please guide me down the right path? I can do this, so feel free to be detailed!