6 minute read
Ignition: Suppressing supposed savings
As with filtration, owner and workshop determinations to cut costs can put the ignition system under extra strain, as Rob Marshall learns
In many ways, modern ignition systems are marvellous –while some technicians lament the passing of contract breaker points and dwell angle settings, many others say 'Good Riddance' to them. Today's ECU-controlled systems have made such regular and fiddly adjustments obsolete but this does not mean that they are maintenance-free.
As with our prior filters article, Delphi acknowledges the trend of some drivers postponing regular servicing, highlighting the need for reliable components that can tolerate not being looked at for long periods. DRiV, owner of the Champion brand, reminds us that skipping servicing is a false economy, which can lead to reduced efficiency and even significant engine damage. Despite this, modern ignition systems do not comprise many moving parts that require routine replacement. Naturally, spark plugs are excluded but even the most basic plug lifespan has at least doubled in the last fifty years. Yet, ignition systems still need periodic checks. Delphi highlights that many parts of the ignition system, such as the spark plugs, HT leads and coil packs work together. Therefore, neglecting routine replacements and visual inspections places all components under extra stress that could shorten their lives.
Champion reports that, even with car owners looking to cut costs, it has not witnessed a significant growth in budget parts, versus OE quality spark plugs. We should be grateful for this, although a possible reason for this is that spark plugs are becoming more application-specific, especially with more recent GDI engines.
Head ruling over wallet
Spark plugs excepted, most ignition parts tend to be replaced once they fail. Meyle continues to view ignition system repairs as a growth area for the aftermarket. It reasons that, despite new technologies being available being offered by carmakers, many customers are unconvinced and choose instead to have their faithful older car repaired, rather than replaced. Meyle cites that, because the average age of a typical roadworthy motorcar is increasing, so too is the demand for spare parts.
Yet, the temptation to cut corners is still present. Hella says that cheap ignition system components introduce higher costs eventually. This is not just down to the cheaper part failing sooner but also the damage it can afflict to other components (such as ECUs), or even the engine. Champion agrees, stressing that most technicians appreciate that inexpensive parts give marginal savings at the cost of longterm expense. Despite this, Meyle reasons that repairs must remain cost-efficient and that car owners desire a good value but this does not mean they prioritise the lowest price, or the poorest quality component. The emphasis must still be on OE quality. After all, an ignition system must provide sufficient energy to the appropriate cylinder, at the right moment, thousands of times a minute. Delphi reports that any number of performance issues will result from the spark being even momentarily late, including misfiring, reduced power and poor fuel economy.
Long-life plugs are especially valuable where access is either difficult, or significant dismantling is needed to reach them
Delphi adds that you should trust the part you choose to fit but evaluating quality of a box-fresh item is not easy. While a cheap ignition coil might look near-identical on the outside, Delphi reveals the unseen benefits of its OE-quality products. These include high-quality wiring, insulation and coatings along with dependable internal windings. Vacuum production ensures also that air bubbles are removed from materials that would cause arcing, or internal short circuits. Comprehensive testing also ensures that the coils can withstand vibration, temperature extremes and moisture exposure for many years. As with many things, the issue boils down to garages and technicians trusting the brand and supplier.
What about upselling?
There are precious few opportunities to upgrade ignition system components, because the priority should be OE quality and matching the right part with the appropriate engine. Yet, keeping abreast of the latest product news remains a worthwhile exercise. While all brands mentioned within this feature are introducing new lines continually, Delphi has brought multi-spark ignition coils into the aftermarket. These units allow the spark plug to increase the spark duration and intensity, due to the coil facilitating multiple sparks within a very short time frame. Multi-spark coils have proven beneficial, especially for GDI engines, and the company claims that they can produce a 20% reduction in fuel economy in addition to smoother engine operation, improved throttle response and enhanced power delivery.
Yet, you can consider offering spark plug upgrades at service time. Champion told us that, on normally-aspirated engines, standard spark plugs tend to utilise copper centre electrodes. These can be upgraded to precious metals for increased longevity and performance. Long-life plugs are especially valuable, where access is either difficult, or significant dismantling is needed to reach them. Hella's copper spark plugs, for instance, have an 18,000 miles life. By adding a centre electrode that is made from Yttrium, this service life is doubled. Finally, by using Iridium, Hella says that a set of plugs can go up to 60,000 miles between replacement intervals.
Doing it right
Even with fast-moving parts, decent-quality components are influenced negatively by poor installation. Hella reports that it still finds garages selecting an inappropriate spark plug for the application, not cleaning away any contamination upon the cylinder head/plug contact surface and not torquing the spark plug to its correct value.
When fitting ignition coils, Delphi advises that incorrect torque remains an issue for mounting bolts. Should they be too loose, the coil becomes exposed to excessive vibration; too tight, the coil body can crack. The company even reports seeing technicians using hammers to install ignition coils - a situation that causes micro-cracking.
Denso also reminds garages that glow plug failure tends to occur as winter approaches.
Champion prompts us not to replace a single failed plug but they should be changed as a set. Hella adds that customers should not forget that a good maintenance schedule can highlight the early phases of glow plug failure. Meyle advises that new glow plugs should be from one manufacturer and that, where it is required, technicians do not omit to programme the glow plug control unit, afterwards.
