What Colour should a good spark plug be?

Normal Condition

If the firing end of a spark plug is brown or light gray, the condition can be judged to be good and the spark plug is functioning optimally.

What color is a rich spark plug?

If the engine is running to rich the spark plug will look black, sometimes a glossy black if it's really rich. The goal is to get a good dark coffee brown color on the spark plug, which represents the correct color on the spark plug itself, and assures you that the Fuel to Air mixture on your carb is set correctly.

Should spark be blue or yellow?

The strength of the spark is revealed in the color. A red or yellow spark is weak and probably will not spark in the cylinder. A blue or white spark is strong and has enough voltage to fight across the spark plug gap even under pressure within the cylinder.

How do I know if my spark plug is good?

What spark plug colors mean?

By examining the insulator firing nose color, an experienced engine tuner can determine a great deal about the engine's overall operating condition. In general, a light tan/gray color tells you that the spark plug is operating at optimum temperature and that the engine is in good condition.

How to "Read" your Spark Plugs | Goss' Garage

What does white spark plugs mean?

If your spark plug is white in color or appears blistered, that means something is making the plug run too hot. Check for problems in your engine's cooling, a lean fuel mixture or incorrect ignition timing.

What does weak spark look like?

Weak sparks are orange or red and may be hard to see in daylight. If you did not see a spark, remove the coil wire from the distributor cap. Attach the spark tester to the distributor end of the coil wire. Crack the engine and check for a good spark at the spark tester.

Should spark plug spark be blue or orange?

Orange sparks are like slow sparks that miss fire and creates other problems, so blue is more effective and that's how ignitions are designed to properly be efficient. Orange sparks could mean ignition problem in the coil, a bad ground or too much resistance.

What does a yellow spark plug mean?

Caution: Running the engine with a lean fuel mixture will cause the engine to overheat and burn the electrode of the spark plugs. Pay close attention to the High-speed Needle adjustment. Running the engine with the proper fuel mixture will make the spark plugs appear yellow at the ignition point.

What does a red colored spark plug mean?

However, don't be dismayed if ceramic insulator tips (center and ground electrodes on a plug) are pinkish-red in color. That pink coloration is created by deposits from additives in unleaded fuel when they're burned off during combustion.

What are signs of a bad ignition coil?

What does a spark plug look like when running rich?

Rich running conditions: If your engine is running too rich, the spark plug will be black and sooty. Lean running conditions: If your engine is running too lean, the spark plug will be white. If the spark plug is black and oily, they are oil fouled.

How do I know if my engine is running rich or lean?

But what is the difference between an engine running rich or an engine running lean? The expression running rich or lean is in reference to the amount of gas that you have in the engine. If there is too much gas, then you will be running rich, and if there isn't enough gas, then you are running lean.

What does blue spark mean?

Just before a plug touches an outlet, when the two are very close to each other, an electrical current from the circuit will reach across the tiny gap and create a spark. This small, blue spark is normal.

What causes weak spark?

A weak spark, or no-spark, problem may originate within one or more common ignition system components: Worn or damaged spark plug wire insulation. At high temperature, this problem can produce bucking or misfires. Dirty or worn spark plug.

What do black spark plugs mean?

Soft, black, sooty dry deposits on plug indicate carbon fouling. What This Means. Carbon fouling is an indication of a rich air-fuel mixture, weak ignition, or improper heat range (too cold).

What does an oil fouled spark plug look like?

Oil fouling of a spark plug typically results in a shiny, black appearance. If enough oil is in the combustion chamber, the deposits can build up on the tip, porcelain or shell. If you can't determine if it is carbon or oil fouling, smell the plug; it will smell like engine oil.

What are the symptoms of a rich fuel mixture?

What does a bad spark plug coil look like?

Once the engine is cranked, you should look for blue sparks along the spark plug gap. If you can see blue sparks, this proves your ignition coil is working correctly. If you don't see blue sparks or you see orange sparks, this is a sign that there's a problem with your ignition coil.