I write about automated technical advancements a lot. I can remember 35 years ago when a tune-up – an adjustment to the engine to improve performance – was relevant.
Before computer-controlled engines, we had to replace spark plugs, distributor caps, distributor rotors, points, condensers, fuel filters and air filters.
Nowadays, the only relevant parts to an engine’s housekeeping are spark plugs, air filters and sometimes fuel filters. Yet the only one you have to change on a regular basis is the engine air filter. Engine air filters are truly victims of their environment. If you live in the country or the desert, you will be replacing your air filter a lot more frequently (every 3,000-6,000 miles). If you live in an environment that gets a lot of rain, your air filters will live twice as long (30,000 miles) compared to areas where there is little rain (15,000 miles). This is because the rain cleans the dust, sand and dirt off the roads and keeps them clean.
Fuel filters used to be small and made of plastic. They used to get replaced every 3,000-6,000 miles. Nowadays, fuel filters are approximately 10 times the size and are made with a metal case. The reason for this is so they can handle the pressure and volume of high-pressure fuel pumps. Because fuel filters are so large, they rarely cause a problem. They usually do not have a mileage interval, yet we will replace them at 100,000 miles or during a fuel pump replacement.
Spark plugs
Spark plugs have also taken a large technological jump. Forty years ago, nearly all spark plugs were a resistor style with a steel center electrode and steel side electrode (ground). These steel spark plugs would last between 15,000 and 30,000 miles. In 1985, Bosch introduced its platinum center electrode spark plug. This was the beginning of the end of the modern tune-up. Once platinum spark plugs took hold, the replacement interval could extend as far as 100,000 miles. Then in 1994, NGK came out with the iridium spark plug that was seven times harder than the platinum ones. The iridium spark plugs can go out to 120,000 miles.
Because the life of spark plugs has been extended so long, people have kind of forgotten about them. When we bring up spark plug replacement, customers always say, “Do we have to replace them?” Many people take the approach that if it’s not broken, don’t fix it. But manufacturers have set mileage limitations for spark-plug life.
Yes, some manufacturers let you go as long as 120,000 miles, but there are others that set it at 30,000, 40,000, 50,000 or 60,000. This is because spark-plug life is determined by hour run-time just as much as mileage, and the ground electrode is still made out of steel. The steel ground electrode continues to wear out even if the platinum and iridium do not.
Driving conditions also play a large role. If your manufacturer tells you to replace the plugs at a certain number of miles, they are doing it for a reason.
Recently we had a new customer bring in his 2018 Audi Q5. The check-engine light was on and the car had a misfire. During the inspection, we found that one of the spark plug ground electrodes had worn completely off. We also found that two of the spark plugs were loose. The spark plugs are supposed to be replaced every 40,000 miles. It was the first time we saw the car, which had 100,000 miles on it. It is possible that the spark plugs were not replaced at the 80,000-mile service. The ground electrode is a larger piece of steel; we were very concerned that it may have caused damage in the engine. So far, the customer has been lucky and the worn-off ground electrode did not severely damage the engine.
Although tune-ups are dead, it does not mean we stop serving cars. Tune-ups have just turned into services and maintenance. Even with more and more electric vehicles on the road, they also require service.
Matt Pataky owns Sunnyvale Foreign Car Service, 15 Pioneer Way in Mountain View. For more information, call (650) 960-6988, email [email protected] or visit sunnyvaleforeigncar.com.
