Can any one tell how much a solenoid cost and what the purpose of it is?

Answer 1

It can cost from just a few dollar to hundreds, A solenoid is a wire coil that when it is energized with electricity creates a magnetic field. In the center of the coil is a iron rod that is drawn forward by the electromagnetic force. When it is actuated it can open a valve that allows the flow of air, gas, water, oil or a solid material. it can also b used to move a mechanical device. Your electric door openers are operated by solenoids. When you turn something on and hear something click it more that likely is operated by a solenoid.

Answer 2

A "solenoid" in general at a auto parts place can be refering to 1 of 2 things, either a solenoid that is attached to the firewall, or a solenoid that is attached to a starter. What they do is turn the little 12v current of the battery into something like 4000v. If its bad you wont get enough power to start the vehicle.

Price ranges can vary, but you cannot replace the solenoid on a starter, generally you need a whole new starter, but for the firewall mounted variety anywhere from 6dollars to 120dollars depending on make/model etc.

Answer 3

http://www.carcare.org/Electrical/solenoid.shtml

Before replacing the solenoid check the starter relay and the battery and clean the battery terminals and posts. NEVER replace a part till you KNOW the problem.