Grill door is controlled by a pair of complex spring-loaded hinges and it seems the springs aren't doing the job - this might be because the hinges are tight, which would be a matter of lubrication, or because the springs are weak or broken.
The hinges usually aren't easy to access so it is best to try lubrication first by spraying with something like WD-40 fitted with a straw so it can reach into the apertures and then work the door for a couple of minutes to see if there is an improvement. Be aware the propellant is highly flammable but it does disperse quite quickly.
If there is no improvement, the hinges will need replacing.
Answers & Comments
Grill door is controlled by a pair of complex spring-loaded hinges and it seems the springs aren't doing the job - this might be because the hinges are tight, which would be a matter of lubrication, or because the springs are weak or broken.
The hinges usually aren't easy to access so it is best to try lubrication first by spraying with something like WD-40 fitted with a straw so it can reach into the apertures and then work the door for a couple of minutes to see if there is an improvement.
Be aware the propellant is highly flammable but it does disperse quite quickly.
If there is no improvement, the hinges will need replacing.