A spark plug is read by examining its condition and color. Learn how to read a spark plug so you can keep track of how your car or bike is running. You can identify potential issues before they become severe and know when to change your plugs for maximum performance.
A. How To Spot Damaged Spark Plugs
Step 1: On A High-Quality Spark Plug, Look For Light Grey Or Tan Metal
A healthy spark plug will appear light gray or tan. There shouldn’t be any accumulation on the sparking surface of the plug. The colors of the spark plugs should be similar if you just bought them.
- A high-quality spark plug will last for a long time.
- A problem with the plug wire may exist if the cylinder has been misfiring despite having a proper spark plug. To test if it fixes the issue, try changing it.
Step 2: Recognize Carbon Fouling Symptoms
When your vehicle engine is running too rich, carbon fouling frequently happens. When the spark plug ignites the air/fuel mixture, running too rich indicates too much fuel. On the plug’s sparking surface, check for black soot.
- When the engine runs excessively rich, black, dried soot may form on the plug.
- The plug can be washed, saving you the expense of replacement. To clean it, use a towel and brake cleaner, or spray it with some.
- It would help to take it to a mechanic to find out why your vehicle runs rich.
Step 3: On An Oil-Fouled Plug, Look For Moisture
The spark plug may be oil-fouled if oil flows from your engine past worn piston rings or through the valves on your cylinder head. On the plug itself, look for any signs of damp motor oil.
Plugs with oil fouling will be wet, whereas plugs with carbon fouling will be dry.
- To stop more spark plug fouling, you must fix the oil leak.
- Having an oil leak in the engine might have serious consequences. Take your vehicle to a technician so they can diagnose and fix it.
Step 4: Look For Burning Or Blisters
You can burn out a spark plug if your engine has overheating problems. Look for symptoms of heat damage, such as charred metal or melted plastic, or blistering on the spark plug’s insulator tip.
- Spark plugs that have been damaged by heat must be changed.
- Outdated or insufficient coolant levels may bring on issues with overheating.
- If your vehicle’s coolant level is low, top it off; otherwise, you might need to drain and flush the radiator.
Step 5: Look For Indications Of Severe Wear
But, a spark plug that has been in operation for too long is significantly worn. Older automobiles with spark plugs that have never been changed may fail without the types mentioned above of fouling.
- When removing a spark plug, severe wear could cause it to separate. Additionally, corroded connections or cracked plastic may show indications.
- Plugs that are severely worn must be replaced.
B. Taking Spark Plugs Out
Step 1: Unplug The Battery
Disconnecting the battery is crucial before working on a vehicles electrical system. By loosening the nut securing the ground cable to the battery’s negative terminal with the proper hand or socket wrench, you may slip the line of the terminal and tuck it away. It will connect the positive wire.
Step 2: Take The Spark Plug Wire Off
Spark plug wires enter the engine through holes in the cylinder head. They link to the spark plugs via an ignition source, such as ignition coil packs or a distributor. Pull back on the wire to detach it by grabbing the base of the plug wire at the spark plug.
- Often, plug wires may pop off with a bit of force needed.
- Avoid pulling on the wire directly since doing so could cause the plug wire to be torn and leave the base of the spark plug connected.
Step 3: Clean The Area Around The Spark Plug Hole
Before removing the spark plugs, ensure the area around the plug holes is free of oil, dirt, or debris. Anything that falls into the recesses of the spark plugs will fall directly into the engine since they are screwed into the cylinder chamber.
- The next time you start the engine, debris that falls into the openings could seriously harm it.
- Before reinserting a spark plug, use a shop vacuum or can of air to remove anything that may have fallen into the holes.
Step 4: To Remove The Plug, Use A Spark Plug Socket
In contrast to standard sockets, spark plug sockets have a rubber cup that retains the spark plug as you unscrew it. The plug can be unscrewed but will remain inside the hole in a standard socket of the appropriate size.
- Spark plug sockets typically fit plugs in most applications, and spark plugs often only come in one size.
Step 5: With The Socket, Take Out The Spark Plug
Turn the wrench counterclockwise until it has finished unthreading, then unscrew the spark plug. The spark plug should remain inside the socket as you carefully lift it out of the hole.
- You should leave the spark plug in the socket while you check if it is still warm.
If you’ve decided to replace the spark plug or are replacing one, stick to these recommendations. After that, you can continue checking each spark plug individually. If your spark plugs need to be changed, you can do it yourself or get help from your dependable technician.