I'm getting my spark plugs replaced tomorrow. I searched Google and on Yahoo Answers some people are saying the spark plug wires should be replaced when spark plugs are replaced. Does anyone have any knowledge or preference on this? Thanks! -2004 Corolla, 179,900 miles, never had a single problem with the car. (my car has Toyota Iridium spark plugs and I think they are the originals (I need to check my maintenance records) Thanks! (if this is in the wrong forum, moderators, please transfer this to correct forum. thanks)
I think your Corolla is new enough to use Coil on Plug technology. My GF's 2001 Avalon uses coil on plug and so does the Prius. If so, you do not have any spark plug wires.
If it is coil on plug, there are boots to replace. At least I plan to do so on the HHR soon. I figure the environment of an engine bay isn't the most hospitable to rubber and plastics, and it's simpler to replace everything at once even if it isn't required. Replacing actual wires would be almost a must though. In addition to the engine heat you have the high current running through them and the insulation will degrade over time. If it does, it can affect drivability. There's an easy test for them by watching for arcing in the dark.
no wires as coil on plug Boots should be fine. A dab of high temp silicone on the boot won't hurt If the wire harness is pooched that is a pricey repair
