I got an old Janome 663 machine. The foot pedal seems to have only 2 speeds, full power and stop, no matter how delicately I press it.
Should there be more control in the foot pedal (I would expect that)?
Is something broken in it, or this is how it operates?
I think that you need to take your machine to a sewing machine technician. I've never known of a machine to have a foot controller that only has a fast or stop. As they are on the floor dust gets in and it probably just needs to be cleaned out.
Saskatoon, Saskatchewan Canada HMC15000, many more sewing machine, and my computer game of DigitizerMBX v.4.5 with Cutwork