What is a tune-up? – Introduction In today's world of electronic ignition and computer controlled fuel delivery systems, the idea of a tune-up may seem outdated. In the past, a tune-up included changing spark plugs and filters, as well as making basic engine adjustments such as timing, idle mixture, and idle speed. However, spark plugs last longer than ever before and recent advancements in engine management systems have made most of these basic adjustments unnecessary. So are tune-ups a thing of the past? No, the tune-up is not a thing of the past, but it needs to be redefined to keep up with the changing technology. That’s why we’ve developed the 21st Century® Tune-up. With the introduction of computer controls, there is a greater need for optimum performance by all the components in the system, including associated sensors, actuators, and other engine components. If even one sensor is out of calibration, it can upset the entire balance of emissions and fuel economy. An engine component failure such as a burned valve can cause major changes in engine operation. The excessive hydrocarbons can overheat the catalytic converter and the extra oxygen will drive the feedback system rich. That is why all parts must work together to achieve peak performance. Performance is the operative word when discussing a modern tune-up. When a motorist brings his or her car in and asks for a tune-up, they are really saying "I want my car to perform better." They do not understand things like closed loop fuel control, electronic spark timing, or idle air control systems, but they do know when their car is not behaving the same as it used to. Symptoms such as cold start problems, surging, poor fuel mileage, and shutting off at stops are just a few of the items that will cause a motorist to come in and ask for a tune-up. The term "tune-up" is familiar to most people. However, its meaning varies from one person to the next. Technicians generally think of a tune-up as evaluating all major systems with advanced diagnostics to ensure that all are performing properly and in sync with each other. A motorist may not think of a tune-up in the same way. After all, if a customer takes his bicycle in for a tune-up, he knows the bicycle mechanic won't install a new crankshaft position sensor, but he does expect the bike to perform better when the work is completed. So when you think tune-up, think 21st Century® Tune-up. Back to Things You Should Know Visit our Resource Library for available downloads