When Contax cameras were being made their cost was astronomical. A Contax IIa with 50mm f2.0 Sonnar sold new for the equivalent of over $5,000.00 in today's dollars. So these cameras were treated with the utmost respect back then. Today they cost considerably less, but if you intend to keep your Contax working properly you must treat it as if it cost you $5,000.00. The reason for this is acceleration and deceleration.
If you take your precious Contax camera and toss it onto the passenger seat when you enter your car it will hit the seat, go down, stop, and then go up. It has been accelerated to a speed of approximately 15 miles per hour, instantaneously stopped, and then reaccelerated in the opposite direction. In doing this very simple thing your camera has been subjected to a cycle of acceleration and deceleration that the camera is instantaneously exposed to at least 15 gravities of force. Imagine what you would look like and feel like after a good 15G shaking! The shutter mechanism has long thin levers in it that are very carefully, delicately, minutely and precisely bent to adjust the shutter speeds. This sort of acceleration/decelaration can easily distort them. So it should not surprise you that if your camera is tossed onto a car seat or somewhere else the next time you use it the shutter speeds will not be quite right.
It is easy to take a Contax apart. Many people have done this. Putting it back together is another thing. A Contax must be carefully assembled over a period of days. Each part and assembly must be put back so that its feel is correct. Each assembly distorts the body a little, and the adjustments are many and tiny. With each assembly there must be a wait to ensure the situation is permanent. Finally the camera is in one piece and every control has precisely the right feel and everything is accurate and reliable. A single toss of the camera can undo all this careful labor in a split second.
The ancient writer Plutarch writes an ancedote about Julius Caesar that illustrates the best way to care for your Contax. He writes that one day Caesar was in the Forum and obseved a group of foreign women all of whom had small dogs with them. Plutarch remarks that Caesar made the comment to his friends, "Don't women have children where they come from?". In this way he indicated his feeling that the women were lavishing the care and love due to a human child on dogs. This ancedote is indirect, but does illustrate that a prudent Contax owner will find his camera to be so precious he treats it like a baby.