The technical optimum

For more than 20 years automobile manufacturers have been using NGK glow plugs as standard equipment. But can these glow plugs be replaced with comparatively less expensive metal glow plugs? The answer: many things “can” be done, of course. The question is, what risk is involved. In cars that have NGK ceramic glow plugs installed at the factory, only NGK ceramic glow plugs should be used when it comes time to replace the glow plugs. The reason: these glow plugs were specially developed for the specific engines; they guarantee a long service life and fast, reliable combustion even at extremely low outdoor temperatures. At the same time, they reduce harmful emissions. Although they at first appear to be somewhat more expensive than metal glow plugs, one should consider the following:

• Metal glow plugs can make it difficult to start a car at extremely cold sub-zero temperatures.
• When changing to metal glow plugs, all of the glow plugs have to be replaced, including those that are intact. If problems arise with the metal glow plugs, a complete set of new ceramic glow plugs has to be paid for.