IT used to be a common sight: average car owners in their driveways on a weekend afternoon perched under the hood fiddling with the inner workings of their car engine.
Times have changed, however, and while some car enthusiasts still tinker with parts, newer vehicles have more electronic systems that make them difficult to fiddle with.
New engines have also seen changes with maintenance, and old-school tune-ups have undergone a bit of a makeover.
Ryan Elm, manager at Derosa Automotive Services in North Vancouver, explains that tune-ups are moving away from the old-school check-ups, including points and condensers, carburetors, cap and rotor, etc., to spark plugs, filters and carbon build-up.
In the old days of carburetors, mechanics would perform throttle body cleanings and take the carburetor off and clean it out. That doesn't happen any more with fuel injection systems.
"There is no getting in there with a toothbrush, so to speak. It's all pretty much done with chemicals at this point," says Elm.
Instead, tune-ups now focus on spark plugs and the preventative maintenance of doing emissions services to eliminate carbon.
"That keeps everything clean and improves fuel efficiency and emissions," he says.
When considering tune-ups, you need to consider the age of the car, says Elm.
The car manufacturer's maintenance schedule will outline when a tune-up is due, but in general, if the car is experiencing poor fuel efficiency, a stumble or rough running, or if you can't remember the last time the car's spark plugs were changed it's worth asking the question, particularly in cars more than five years old, he notes.
"We have some people come in that say they want a tune-up and what they are actually asking for is an oil change and someone to look at their car and tell them it's OK."
Tune-ups traditionally focused on the ignition or electrical part of the engine components, replacing those and checking the engine timing.
"With the older cars you do spark plugs, which new cars still have, you do ignition wires, the distributor cap and rotor where the electricity would be distributed through in proper sequence or timing; you would check the timing on the engine to make sure that everything is being distributed when it's supposed to be, and probably change the fuel filter and an engine air filter and that just lets the fuel and air flow and burn properly," explains Elm.
The newer types of cars now have electrical ignition coils that bring the electricity straight to the spark plug.
"There is no more timing in that sense. It's all now done with sensors and direct electricity straight from the spark plugs," says Elm. "So when you do a tune-up on a new car, it's really just changing the spark plugs and air filter if need be, and maybe a fuel filter, but the in-between of distributing the electricity has kind of gone away. And that's just extra parts that would wear out and eventually give you a rough running and fuel efficiency problems."
Back in the day, copper was common for spark plugs, but it wouldn't last long.
"With the older style of vehicles, you're looking at doing spark plugs usually every 45,000 or 50,000 kilometres," says Elm.
That's because the older copper spark plugs wear out a little bit as they burn the fuel and the gap that the spark jumps to generate the spark and the electricity and burn the fuel slowly gets bigger and bigger as the electrode on the spark plug wears.
More recently, cars use platinum spark plugs. Platinum is a much harder metal, it's more precious so it's more expensive, but it lasts longer. Depending on the design drivers can get from 100,000 to 160,000 kilometres from a platinum spark plug, says Elm.
The newest spark plugs are made from iridium and are supposed to be good for 190,000-200,000 kilometres.
"I personally wouldn't leave a spark plug in a vehicle that long because if you don't go to touch it until that kind of mileage, the chances of it being seized or stuck in the engine are pretty good and so if you can't get it out and/or in attempting to get it out 200,000 kilometres later it snaps or breaks, now you've got to split that engine in half to deal with it," says Elm.
With newer vehicles the amount of time between tune-ups is getting longer, but a newer problem is developing that existed in the past but is now becoming more of an issue: carbon build-up.
When the vehicle burns fuel and air it leaves small deposits inside the engine on the intake, the combustion chamber, on the valves, etc. Carbon build-up can affect air and fuel passages so that a car can't mix fuel and air properly and it will start to run rough.
"We've seen an engine stop. Flat out not run," says Elm.
There was so much build up that a valve that is usually about two-and-a-half inches wide had shrunk down to the size of a pinky finger and bits of the carbon broke off. The bits went into the engine and stuck some of the valves that open and close for mixing fuel and air so the engine couldn't run.
"Regular servicing with a good shop will lead to the subject of tune-ups coming up," notes Elm.
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