tigger03 wrote:what do the distributor cap and rotor do? what does is the PCV valve, and what does it do??
The distributor cap/rotor are part of your ignition system. They are what essentially delivers spark to each spark plug wire (Which then feeds to the plug). The cap is just a piece of plastic, and does wear / develop cracks.
The PCV valve basically allows unburned gases to go back into the intake to be reburned. There is a more complicated explanation - but that's as simple as it gets. It's fairly cheap - under $10 to replace - but doesn't go bad very often.