Whats wrong if pfaff expression 3.5 sewing machine is squeaky and what should i do

SOURCE: Brother Sewing Machine model:CS8150 bobbin thread problems

The top of the machine is not threaded correctly. First raise the presserfot then rethread the machine. Bottom looping is usually caused by a lack of top tension. There could allso be a bur on the hook.

SOURCE: Pfaff sewing machine 463

how do you thread a Pfaff sewing machine

SOURCE: PFAFF Varimatic 6085

did you get any feedback on this machine's problem?
i'm getting the same model by the end of the week.
thank you. chuck

SOURCE: Pfaff triptronic 2040 sewing machine

Could be a couple of things:

1. Foot control is bad - take foot control to your local Pfaff dealer to try on one of their machines. If their machine won't run either, it's the foot control and you can look into repair/replacement.
2. Machine has a short or some type or computer board problem - take machine to local Pfaff dealer and try with one of their known working foot controls. If the machine still doesn't work, your dealer will need to diagnose what is wrong.

SOURCE: how do you adjust timing on pfaff 138 sewing machine

Take the foot off the machine
Remove the needle plate
Remove the feed dogs
rotate by hand until the needle is at the lowest position
continue rotating until the needle rises 2 mm
the hook assembly should be passing exactly by the scarf of the needle
if not loosen the two screws that secure the the hook assembly and rotate the hook assembly by hand until it is exactly at the scarf of the needle and the distance between the hook and the scarf is .1 mm (almost touching the needle)
tightened the two screws, replace the feed dogs and foot and it should sew perfectly