Tune up

Getting your car a "tune up" means to have the different systems working together properly and effeciently. A car that needs a tune up will use more gas, oil and could damage the engine, cause future expensive repair.

The term "tune-up," it seems, is almost universally agreed by technicians to be archaic. In older cars it meant cleaning the battery cables, servicing the heat riser, pulling the distributor, tearing it down and resealing it where applicable, renewing the points and condenser, then giving it a spin on the distributor tester, cleaning the choke mechanism, checking and adjusting the choke and pulloff, sticking in a fuel filter and a set of plugs, and usually adding a cap, rotor and wires. After the parts are installed, a final dwell and timing adjustment, then set the idle, fast idle, and air/fuel mix.

Of course, there's nothing to adjust these days. So, do we have a tune-up at all anymore? Today's cars aren't maintenance-free just yet, but they're certainly low-maintenance compared to days of old.

Filters

Filter services include charcoal canister filters that are often hidden and easy to forget. These need to be replaced about every 30 months or 30,000 miles.

Air filters

The actual service life varies considerably, depending on the climate and conditions. In severe duty, it may be necessary to check them weekly, or even daily, but unless you're driving around in a dust bowl at high speed, generally checking them at oil change intervals (three months or 3,000 miles) and replacing them every two years or 24,000 miles will suffice.

Spark plug

Spark plug design has improved dramatically over the years, all of us are aware. Single platinum, double platinum, iridium, yttrium, fluted electrodes -- you can get just about anything you want.

Of critical importance is heat range, since a plug that runs cold will foul and one that runs hot may contribute to abnormal combustion processes.Chang standard plugs at 30 months or 30,000 miles, and double that for premiums, such as platinums.

Fuel filters

I'm not a fan of lifetime or extended-life fuel filters. Certainly, there are returnless systems that only filter the fuel used in the engine, but the majority of the systems out there are of the return type, capable of pumping thirty gallons of gas per hour forward to an engine that only uses two or three gallons per hour. All that recirculation means refiltering, and filters plug sooner. Replace fuel filters at 30 months or 30,000 miles, whichever comes first.

PCV valve

Its function is critical to oil cleanliness, long-term ring life, and the normal crankcase pressure that doesn't cause seams to leak. Better oils and combustion chamber sealing have stretched the interval, and, since it's low-tech, we ignore it. But it needs to be replaced every 30 months or 30,000 miles just the same.

Throttle bore, upper intake and EGR passages

Clean the throttle bore and upper intake every 24 months or 24,000 miles. Also check and clean EGR passageways at that interval, particularly on those engines with a problem (older high-mileage 4.6L Fords and 3.1L GMs).

Fuel injectors

Clean injectors at 30 months and 30,000 miles. Even tiny deposits can interrupt flow, and three-to five-percent variance in flow can create performance issues. In addition, a very minor accumulation of deposits on the backside of the intake will disrupt cylinder filling and volumetric efficiency, further degrading engine performance.