The purpose of the Traction Control system is to maintain traction during hard acceleration. Traction Control system monitors the speed of all 4 wheels. If any of the drive wheels begin to slip during acceleration, Traction Control system individually applies brakes to the slipping wheel(s) and reduces engine power.
When Traction Control system operates, you might feel that the engine power is reduced and hear some buzzing. The Traction Control warning light may also flash. A Traction Control system cannot help in all possible situations; for example, if a car is stuck in loose, wet snow, it might be easier to free it out by turning the Traction Control OFF and letting the wheels spin freely to cut through the snow for better grip.
A water pump is an important part of the engine cooling system. A water pump moves engine coolant (antifreeze) through the engine cooling system, thus providing the coolant circulation between the radiator and the engine. A water pump is usually installed on the engine cylinder block. It pulls cooled-down coolant from the radiator and pushes it through the passages (water jackets) in the engine cylinder block and the cylinder head and again out of the engine and into the radiator. This helps keep the engine from overheating; the hot coolant passes through the radiator where it cools down and then returns back to the engine.
A water pump is usually driven by the engine through a drive belt or a timing belt. A water pump consists of the housing with the shaft rotating in a bearing that is pressed into the housing. An outer end of the shaft has a flange that is used to hold a pulley. A serpentine or timing belt runs over the pulley. At the outer side there is a pulley mounted on the shaft. At the inner side there is a seal to keep the coolant from leaking out and the impeller that acts like a centrifugal pump.
Typical water pump problems include coolant leaks, noisy or defective bearing, damaged or corroded impeller. A faulty water pump might cause the engine to overheat, which can result in serious engine damage. If defective, a water pump is replaced as a unit.
Sometimes you might be suggested to replace the water pump at the same time the timing belt is being replaced. In cases when a water pump is driven by a timing belt it's worth to do because it involves very little extra labor, plus, a water pump is subject to wear anyway. As long as the original parts are being used, I'd recommend to go for it.
The wheel alignment is the measurement of the angles of the wheels related to each other and to the car's body. In simple words, all wheels of the car must be close to parallel to each other and perpendicular to the road surface for a car to handle properly. Each car has very precise specifications how the wheels should be aligned. If any of the wheels is not aligned properly a car may have some issues with the handling. Improper alignment can also cause increased tire wear. In certain cases a car may even skid because of improper wheel alignment. The wheel alignment can be measured and adjusted on a special alignment rack.
Over time, parts of the vehicle's suspension and steering wear out and the wheels become misaligned. The wheel alignment should be checked after the vehicle has been involved in an accident, even a minor one. Even if you hit a curb or a big bump the wheels can get misaligned. The wheel alignment must be re-adjusted if certain parts of the vehicle's suspension or steering are replaced. Also, if you feel that the car doesn't hold the road well or it's difficult to keep it straight, or if the car pulls to one side or if the steering wheel is out of center, the alignment should be checked. Similarly, if you feel that the car jumps sideways or fishtails when driving on a rough road, it's recommended to check the wheel alignment.
Before performing the wheel alignment a mechanic usually checks the suspension and the steering components. If any of the suspension or steering pats is loose or defective, it must be replaced before the wheel alignment. Adjusting the wheel alignment is usually not very expensive, and properly done wheel alignment makes a big difference in the way the car handles