Fired up the oven for the first time, Burns fine until you close the door then it get noisy and highly erratic burner flame patterns, open the door and it calms down. So appears to be a combustion air issue. Cleaned the flue out, as there was quite a collection of stuff had fallen in there over the years. My manual is just a user manual - no diagrams or part numbers.
does the oven have another gas regulator behind the oven?
Where are the combustion air openings?
Where is the air shutter that some forums mention?
Burner access is severly limited unless the shelf above it somehow comes out.
Maybe this troubleshooting chart will help.
Troubleshooting: The Magic Chef Oven & Range (https://www.smithsrvcentre.com/page/how-to-troubleshoot-the-magic-chef-oven-and-range)
Magic Chef CGS1740ADH Installation Manual (Page 7 of 11) (https://www.manualslib.com/manual/645223/Magic-Chef-Cgs1740adh.html?page=7)
The air intake is under the oven in the rear. I dont Think the air shutter has anything to do with the oven air intake . It is for tuning the flame color/heat/mixture.
after putting my smartphone camera under the burner shelf, it comes out by forcefully shoving the shelf backwards 1/4" and then lift up.