How often should they be changed? Is it something I could do myself at home? Sorry if this has been answered before (search isn't working[:@]).

 

Ideally, yes, that is something you can do in your driveway, although the plugs in these cars weren't installed from the factory with anti seize lubricant on the threads, so in alot of cases, they are real difficult to remove, and have been known to break off flush with the head, leaving the rest of the plug in the head. There is an actual procedure to "persuade" them out, highly recommended to follow it should you remove your plugs. (When the search feature is up and running again, find it, or someone who has it can post it up or link it). Alot of people are removing them, putting anti seize on the threads, and re installing them to proper torque.

I also believe these plugs are good for 100,000 miles, or close to it.

 

Ok well I had the dealerships take a look at them while chaning the oil today. It was arked somewhat (less than a 1/4 inch). He said I should replace them and all wires (for $150 not happening). I don't know much about cars so I don't know if they really should be replaced or not... If they should be good to 100,000 and all ready going bad I'll raise hell at the dealership to replace them under warrenty.

 

Was the car running like crap lately? Why are you having them checked? I'd be very wary of that dealer, unless I'm not getting the full story....

 

It has been getting awful gas mileage (13-15 mixed hwy/city) so I had the fuel filter changed and told them to look at the spark plugs. The car only has 20k miles on but it is almost 3 yrs old. The plug appeared to be arked about 2 lines down in one place.... Idk if it needs to be relaced or not.

 

True, and they are not supposed to be installed with antiseize on the threads!
True, not because there is no antiseize on the threads but because the electrode shield gets bonded into the head with carbon.
False! Do not put antiseize on the threads. You are only supposed to coat the outside of the electrode shield. If you put antiseize on the threads, any solvent that is squirted into the spark plug access hole that is used to try and dissolve the carbon on the electrode shield wont make it past the threads of the spark plug to the carbon on the shield that is locking the spark plug in place.

 

Thanks for the info, I stand corrected, sorry for the wrong info.