Proper maintenance and tune-up is the key to long and trouble-free vehicle life, and the work can yield its own rewards. The vehicle's Powertrain Control Module (PCM), a computer that controls most driveline related functions, controls many of the functions that at one time, were considered part of a standard tune-up. Mixture adjustment and engine ignition timing are now all controlled by the PCM. No adjustment is possible on these systems. Engine valves no longer need periodic lash adjustment since they are hydraulic and no adjustment is required. So underhood tune-up has taken on a new meaning, generally being centered around engine oil and filter changes, spark plug changes and maintaining the cooling system. Owners are encouraged to set aside time to check or replace items which could cause major problems later. Keep a personal log of services performed, how much the parts cost and the exact odometer reading at the time of service work. Keep all receipts for such items as engine oil and filters, so that they may be referred to in case of related problems or to determine operating expenses. These receipts are the only proof you have that the required maintenance was performed. In the event of a warranty problem, these receipts will be valuable.
The literature provided with your vehicle when it was originally delivered includes the factory recommended maintenance schedule, found in the owner's manual. If you no longer have this information, replacement copies can usually be ordered from the dealer. A maintenance schedule is provided later in this section, in case you do not have the factory literature.
A number of labels will be found underhood with warnings, cautions, fluid specifications for coolant and accessory drive belt routing. A few examples are given here.