Long ago, when cars and trucks were equipped with carburetors, regular tune-ups were a necessity. Engines needed to be adjusted in order to improve fuel efficiency and performance. Today, few people need to have their vehicles “tuned up.” Contemporary automotive design has all but eliminated many of the mechanical parts that once needed adjustment.
In this article, we’ll explore the myth of the tune-up in more detail. We’ll begin with the reasons your car is unlikely to need tuning in the first place. I’ll also note the components that should be checked on a regular basis, including those that directly influence your engine’s performance.
Dismantling A Common Automotive Myth
The purpose of a tune-up is to adjust certain components that have, over time, edged away from their once-precise settings. In older vehicles (i.e. those built prior to the 1980s), such components affect ignition timing, idle speed, emissions, and other key functions. The problem is, today’s vehicles are equipped with computers that control these functions. There is essentially nothing to adjust.
So, why are tune-ups still offered by dealerships and local repair garages? In some cases, mechanics correctly apply an updated definition that is more appropriate to the service. Hence, the work they perform (covered in more detail below) is valuable. In other cases, such as when dealerships promote their “5-Year Tune-Up Service,” the goal is to increase the service center’s revenue.
Important Engine-Related Items To Address
As you drive, your vehicle’s powertrain control module (PCM) monitors the operation of your engine. If any problems occur, even those that escape your notice, a trouble code is generated and stored in the computer. These trouble codes correspond to specific faults and provide clues regarding which components caused them. For this reason, consider investing in an OBD-II trouble code scanner to pull the codes. You can purchase one for less than $40 at most auto supply stores.
There are several other engine-related functions you should check. For example, check for compression leaks and problems with the ignition timing. Take a look at whether your car’s exhaust emissions are meeting your state’s standards. Check the idle speed, exhaust gas recirculation (EGR) system, and the voltage produced by the battery. These are the main items to address since they have a significant influence on your engine’s performance.
Other Items To Check (And If Necessary, Replace)
You should also take the time to closely examine the hoses and belts. They’re made primarily of rubber, so they wear with use. Depending on the length of time that has passed since your last “tune-up,” consider replacing the spark plugs and filters (i.e. air, oil, fuel, and breather filters). These components are often neglected, but will impair your engine’s operation as they become dirty, clogged, or fouled (as in the case of spark plugs).
Lastly, test the distributor cap and the rotor. A large portion of both parts is made of plastic, and thus can develop cracks. Moreover, corrosion can form on the contacts, which may cause intermittent misfires.
Should You Replace Your Car’s Oxygen Sensors?
If your vehicle rolled off the factory floor during the last decade, its oxygen sensors will likely last over 100,000 miles. This, of course, assumes you’re driving in “normal” conditions. A lot of dealership technicians strongly recommend replacing them every 50,000 miles, but this is excessive.
First, replacing oxygen sensors typically costs a few hundred dollars. It’s an expensive job. Second, if a sensor malfunctions, sending bad data to the powertrain control module and causing higher emissions, the fault will generate a trouble code. Thus, unless your OBD-II scanner pulls a corresponding code from your car’s diagnostic system, there is rarely a justifiable reason to replace the O2 sensors.
To recap, your vehicle does not need a traditional tune-up. Instead, it needs ongoing preventative maintenance to ensure your engine performs as smoothly and efficiently as possible.