Dec 3, 2010, 05:31 PM
Personal Sales Rating: (1
Join Date: Jul 2007
Location: Southern New Jersey
Drives: 2013 Mazda CX-5 Grand Touring
How-To: Replace Spark Plugs
Replacing spark plugs is a quick and easy task. Looking closely at the old plugs can also be a great indicator of what's going on inside your motor.
Step 1: Gather your tools and new plugs
- Denso OEM Iridium Spark Plugs (Denso Part# K20PSR-B8; Part # MN163807)
- Spark plug or 5/8" socket & 10mm socket
- Socket Extension
- Anti-Seize Compound
- Torque Wrench (ideal) and/or regular socket wrench
- Canned Air
- 20 - 30 minutes of your time
Step 2: Pop the hood and remove the spark plug cover to expose the ignition coils:
To remove the cover you could use either a Philips-head screw driver or a 10mm socket. Once the cover is off, use canned air or some shop towels to remove excess debris from around the ignition coils.
Step 3: Remove the ignition coils:
It's best to change the plugs one at a time so that you don't get the ignition wires confused and screw up the firing order. So pick a coil and use the 10mm socket to remove it. As you're pulling it out, you'll hear a suction cup sounding "pop". Gently unplug the coil wire harness, remove the ignition coil and set it aside in a clean place.
Step 4: Out with the old
Use your socket wrench and extension and remove the old plug...it may put up a little fight. If you have a spark plug socket, you can simply pull the old plug straight out. If you just have a standard socket, loosen the plug as much as you can and use a length of 1/4" fuel hose to reach down and grab the end of the plug to get it out.
Step 5: In with the new
NOTE: It is not necessary (or even recommended) to change the gap of Iridium spark plugs since the tip can be damaged quite easily.
Put a very small amount of anti-seize on the threads of the new plug and begin to screw it back in and tighten it to 18 ft./lbs. DO NOT OVER TIGHTEN THE PLUG! Replace the ignition coil & wire harness and screw it back in (gently since it's plastic) and move on to the next plug. .
Step 6: Clean up
Put your spark plug cover back on and make sure you don't leave any tools under the hood! That's it...you're done! Here's a reference chart you can use to check the condition of your used plugs: http://www.aa1car.com/library/reading_spark_plugs.jpg
"Speed has never killed anyone - suddenly becoming stationary, that's what gets you."
- Jeremy Clarkson