Since the 1980s, tune-ups are much less intensive then the days when frequent visits to the garage amounted in regular replacement of spark plugs and fuel-air mixture adjustments. Now, our vehicles are controlled and monitored by computers and sensors that tell us what needs tuning or, to a great extend, tune the items themselves.
It would be nice to think that we live in a utopia with self-service cars but computer mechanism in our vehicles only go so far. Regular tune ups are necessary for every vehicle, but the recommended intervals are dependent on the manufacturer, car make and model, and the conditions under which it has been driven.
The modern day tune-up is designed to keep your engine running efficiently and smoothly, which involves replacing the air filter, fuel filter and spark plugs as required. Sometimes a fuel-injection service is required and always have all the fluid levels checked and topped off. Essentially, it's a service that goes above and beyond the regular oil change.
Because each vehicle's service requirements vary greatly from manufacturer to manufacturer and year to year, most maintenance checks are conducted during an oil change. And although it seems tedious, the last word on how often each part and system should be tuned up comes in the form of the owner's manual. Not all service technicians will know that your Kia needs a tune-up every 37,000 miles—more often than your Jaguar, for instance—so the manual is handy for getting a clear picture of necessary services and their intervals.
Finding a competent technician is the key to consistent and reliable tune-ups every time. A good shop will, like a doctor, take a good look at all of the major systems and get a good picture of where the car has been, what its persisting problems may be and what needs to be done immediately.
In the absence of a servicing paper trail, your mechanic can have a full look around the vehicle and start fresh with a diagnosis of the services that need to be done right away and the ones that are coming up around the corner.