Believe it or not the traditional troubleshooting charts should be leading you to mistakes.

How is it possible? It is easiest than you may figure out!

A very common way to diagnose an engine is by looking the spark plug firing tips because its appearance can reveal if your engine has a problem that need correcting.

But you need to be aware that the same spark plug firing tips appearance can have different root causes:

A) Mixture or timing misadjustment or other probable mechanical troubles.

B) Different traffic, weather, particular driving and /or engine operating conditions among others that affects the performance.

Unfortunately the traditional spark plug troubleshooting charts, only are considering as possible trouble causes: the first list A, for each spark plug firing tip appearance.

Never had included in its diagnostics that when the vehicle is functioning in one or some of the conditions listed in B, (that are very often); the combustion chamber temperature is affected, making that the stock spark plug heat range results too hot or too cold for these operating conditions, consequently their tip appearances will show those effects, which could be confused with the effects of mixture or timing misadjustment or other probable mechanical troubles.

For example: in a vehicle that is towing a trailer in a heavy city driving have to perform a extra engine’s charge to fight against the resistance of the weight, very often should overheat and it is not due to a wrong regulation or a mechanical trouble, neither because the radiator is not enough big. It is simply because the stock spark plugs, suggested by the manufacturers at the production line results to hot to this operating condition.

The different operation conditions that infludes in the operating conditions of an engine are much more frequents than most of the people may figure our, as reveals a report of the US Department of Transportation – DOT.

As result of this lack of information, the true importance of the heat range of the spark plugs becomes in a confused and uncertain concept, never sufficiently taken into account.

Forasmuch, it should not surprise that even experienced mechanics are making wrong diagnostics, because most of them are confusing a lean mixture with an overheated spark plug owed to some operating conditions, like hauling a trailer; because the appearances of its firing tips look exactly the same. They can not either distinguish when the stock spark plug results too cold for some particular driving or operating conditions, like when driving at consistent low speed; from when has a rich mixture, because both have the same carbon fouled firing tips appearance.

And the worst! Those wrong diagnostics are leading them to wrong solutions, engaging in repair nonexistent and expensive mechanical troubles or unnecessarily trying to adjust the air-fuel mixture; instead of simply customizing the spark plug heat range to the particular driving or operating conditions that is the unique right, fast and cheap solution.