Spark Plug Types
There are five basic types of spark plugs: standard, copper core, power tip, resistor, and platinum.
- Standard Spark Plug -- the standard plug is used in most applications and contains no unusual design features.
- Copper Core Spark Plug -- contains a copper core inside the center electrode. This permits better current flow though the plug for a better spark. The plug also runs cooler because the copper core expels heat faster than a solid metal electrode would.
- Power Tip Spark Plug -- has a wide heat range. This means the plug can operate well under light load, low speed engine conditions or heavy load, high speed conditions without fouling. Fouling would ordinarily cause preignition or knocking. These plugs have extra long insulators that extend from the bottom of the plug.
- Resistor Spark Plug -- the resistor plug appears much like a standard plug, but it has a 10,000 Ohm resistor between the terminal and center electrode. The resistor decreases the current in the spark, thus slowing electrode wear. It also eliminates static that would occur in the radio. These plugs are most common in modern vehicles.
- Platinum Spark Plug -- has a platinum center electrode for quicker plug warm up. This reduces spark plug fouling during cold engine driving. These plugs have a long life and are also essentially maintenance-free; they do not require periodic cleaning or regapping.