by Pep Sanchez
Last time, we talked about the nuances of scheduling your oil changes and the expose on the purported benefits of high-octane fuel (riveting, I know) but today, we will continue talking about a few more of car care techniques that had proven to be scandalous lies (or at least plain outdated if we have to be less dramatic about it).
Once more, let's dive in.
Warming-Up Your Engines.
Here’s a favorite: you need to warm-up your car engine before driving. So is this true? On modern gasoline cars, no it’s not needed. Understanding why this notion is prevalent, a short history lesson is in order.
Warming-up your engine is a throwback of the times when cars had carburetors. Carburetors is basically a device that allows fuel to leak into the intakes (that’s a rather clumsy shorthand explanation but you get the idea). When the engine is starting cold, fuel does not vaporize well enough in a carburetor to make for a good air-fuel mixture needed for efficient combustion.
An engine warming-up will run rich in fuel at first (via a mechanical process called choking) in order to reach a higher operating temperature and run better and smoother.
But with the advent of electronic fuel injection and advanced engine sensors measuring a plethora of variables such as ambient temperature, intake levels, air-fuel mix and exhaust oxygen levels, engines can now compensate with cold conditions when starting up, making warming-up the engine a thing of the past.
Another reason why people insist with warming-up the engine is the notion that cold engine oil needs to be heated to lower its viscosity and provide better lubricity. It also allows the engine to wash its internal with engine oil before having it do the demands of driving. Sure, you may want to give the engine a few seconds to circulate oil to its parts for initial lubrication but modern engine oil itself is stable and useful from the cold in most environments. Just make sure your engine has the correct grade oil as recommended by the OEM.
There are reasons why you would want to leave your car several minutes on idle before driving off to your destination, like warming or cooling the car interior for passenger comfort, but it's unnecessary if you’re doing it for the engine’s sake. So unless you’re driving a car that was made in the mid-90s or older (right about the time EFI became standard in gasoline-fueled cars), your car is always good to go, even from dead cold.
Another automotive car care practice still thrown about but doesn’t really hold much water nowadays is the term engine “tune-up”. It’s a catch-all maintenance term at best, and at worst, a misnomer: another throwback of the time when good ol’ cars ran on carburetor and mechanics didn’t need a degree in computer programming (that last bit is a stretch but I’ll get to my point).
Back in the day, the variables of a car’s normal operation, such as idle speed, ignition timing, air-fuel ratio, were all governed by mechanical systems. These often need periodic manual adjustments by a mechanic to ensure that the engine would run most efficiently.
But in the modern car, all these variables are monitored and controlled by computer systems. Also called electronic engine management system, this comprises of a multitude of sensors for monitoring operating aspects of an engine, a central control module which interprets the data and makes hundreds of split-second adjustments via an array of actuators in the engine. Examples of parts controlled via actuators are the fuel injectors of the fuel system which pretty much replaced the carburetor in the modern engine.
This means a modern engine tunes itself to run optimally every time, all the time. So if a tune-up is an antiquated procedure, what do people (and sometimes even mechanics) recommend it for your modern car?
Going for a “tune-up” now means having the physical parts of your engine checked for wear-and-tear. It may include having your spark-plugs or fan-belts inspected for wear, electrical wiring and battery condition tested, and if your auto repair shop really cares for your car and personal well-being, brakes, window fluid and wipers, tire condition and other basic safety features would be all checked as a standard procedure.
So the next time your mechanic or local auto repair shop advise that your car needs a tune-up, see what they exactly mean by it just to make sure they know what they’re talking about.