TUNE UP

TUNE UP

The word Tune-up is actually an obsolete and outdated term. Yet many people think their engine still needs a tune-up. What they actually need is preventive maintenance

The only engines that still need a tune-up today are of the 1970 and back with carburetors and distributors.

TUNE UP CHECKS

A simple maintenance type tune-up (a new set of plugs) may make an engine easier to start, improve fuel economy, lower emissions, restore lost pep and power if the spark plugs are worn or fouled

An engine check-up should start with a scan for any current, pending or past fault codes. This requires plugging a scan tool or code reader into the vehicle diagnostic connector so the tool can communicate with the powertrain control module (PCM). The onboard diagnostic system

If no faults are found, and the engine is running normally there are additional things that should also be checked

ØBattery voltage
ØCharging voltage
Ø Power balance or dynamic compression
Ø Engine vacuum
ØOperation of the fuel feedback control loop
ØCheck exhaust emissions
ØVerify idle speed
ØCheck ignition timing -- if possible
ØOperation of the EGR valve

addition to these performance checks, hoses and belts should be visually inspected
All fluids (oil, coolant, automatic transmission fluid, power steering fluid and brake fluid)

WHAT TO REPLACE

ØSpark plugs
ØRotor and/or distributor cap (if required)
ØFuel filter; Air filter; PCV valve and breather filter
Ø Other parts on an "as needed" basis (things like spark plug wires, belts, hoses, fluids,)
Ø Check and adjust

OXIGEN SENSOR

late model vehicles should last 100,000 to 150,000 miles under normal driving and operating conditions The oxygen sensor is a key sensor that can hurt fuel economy if it is getting old or has failed. Oxygen sensors are expensive to replace. They typically cost $35 to $70 each, and some may cost upwards of $200 or more depending on the application. The recommended replacement interval for unheated 1 or 2 wire wire O2 sensors on 1976 through early 1990s applications is 30,000 to 50,000 miles. Heated 3 and 4-wire O2 sensors on mid-1980s through mid-1990s applications should be changed every 60,000 miles.

CLEANING FUEL INJECTORES

Dirty fuel injectors are a common problem that can hurt engine performance, fuel economy and emissions. The cure is to clean the injectors and valves. Cleaning is recommended for any engine that is suffering a performance complaint or has more than 50,000 miles on the odometer. Cleaning the throttle body can also help eliminate idle and stalling problems that plague many of today's engines

THE 100,000 MILE "NO TUNE-UP"MYTH

The spark plug replacedment interval on most late model engines with platinum or iridium spark plugs is 100,000 miles. Regular oil and filter changes are still necessary to maintain proper engine lubrication. Most experts still recommend changing the oil and filter 3,000 miles or three to six months. Today's 100,000 mile tune-up interval also skirts around the issue of fuel filter and air filter replacement