Buying cars

This is a subject I get asked about a lot, being a car guy and all that. So I'm putting this guide together to explain the process of buying a car, including deciding what you want, inspecting for mechanical trouble, making the purchase, and getting it legal. I'll give advice on the specific brands I and my family have owned, and do my best to provide commentary on others.

It's also likely that my car friends will contribute to this page as well, so expect frequent updates.

What do I want?

There are tons of factors that go into choosing a car. A car is a very personal belonging and also a considerable investment, so you want one that works well for you. There's a lot to consider, but the main factors for most people are:

Target audience

I'm targeting people who have a budget of about $10,000 or less. If you are willing to spend more than that on a car, much of this article can be ignored. Go to a dealership and buy something new or certified pre-owned that fits your budget and needs, and if it breaks while under warranty, take it to the dealer and make them fix it.

Driving mindset

For many people, driving is a necessary evil. You would rather be riding somewhere, instead of having to do all this work to navigate a 3,000 pound hunk of metal and plastic to your destination by yourself.

I'd like to actively challenge this. Driving isn't an evil, but an opportunity. It's the opportunity to master a machine, to execute skilled maneuvers, to control and navigate to your own destination, quickly but with the greatest possible regard for safety and stability of the vehicle, as well as the people and cars around you.

I'm a firm believer that a car is more than the sum of its parts; it's an expression of you, and when you're driving it, it becomes an extension of your body. A car can be a work of art, a companion, a challenge to master. Whatever your car is to you, embracing the art of driving and focusing in on it, instead of zoning out, will be better for your own long term health as well as that of your vehicle.

Body style

Vocab:

A lot of people have said they want an SUV for the extra storage space. The idea that SUVs have more space is largely a myth. A Jeep Grand Cherokee has only marginally more cargo space than my tiny little VW GTI. The additional ground clearance of the jeep means the wheel wells protrude less into the passenger compartment, which adds a few cubic feet, but honestly, it's not a whole lot.

This is really important to consider if fuel efficiency is an important factor for you. A small hatchback built with the goal of being a gas-saver will hold almost as much as an SUV, but at half the fuel cost. Seriously! A fuel-efficient four-cylinder car will usually drive 30-40 miles on a gallon of gas (MPG). An SUV, especially one from the early 2000s, is more likely to be in the 16-22mpg range.

Many people feel safer if they are driving higher off the ground. While this is a valid complaint, remember that most cars on the road today are short cars, and even in a small car, you're never going to be so small that someone in an SUV or pickup won't see you. Drivers of semi trucks go through a lot of training before they receive their licenses to operate big rigs, and even if they can't see you directly, they know where to look in their mirrors for you. Shorter cars also won't roll over, and will provide better cornering and handling than SUVs in many cases.

If you need to haul a lot, get a station wagon. These are basically full-size sedans with even more space in the back.

Why get a small car?

For some people, a small car really is all you need. Most small cars can haul up to 5 people. If you spend most of your time with only 1 or 2 people in the car and don't need to move stuff around a lot, get a small car. They're easier to park in small spaces and a million times more fun to drive than large cars.

Styles to avoid

I'm really critical of crossovers, because they tend to have the cramped interior of a small car combined with most of the top-heaviness, poor cornering, and inefficiency of an SUV. While there are exceptions to all of these rules in the CUV world, I don't know of any cheap crossover that provides all three of solid handling, space, and efficiency.

On the hatchback

Both of my cars are hatchbacks. There's a good reason for this.

I love the sporty handling, tight cornering and solid construction of a smaller car, but I also frequently haul my keyboards to gigs and travel out of town to visit family and friends. Hatchbacks can be incredibly fun cars to drive while still having a huge amount of utility.

When to get a tall vehicle

If you have to drive on dirt roads or exceedingly poor blacktop to get to your home or workplace, limit your search to SUVs, CUVs, and pickup trucks. Even if a smaller car can clear the ground, severe rain or snow may make the terrain impassable, and you will wear out the suspension on a short car more quickly.

Transmission

The choice of transmission is probably the second most personal aspect of narrowing the scope of cars to buy.

Regardless of whether you have an automatic or manual car, learn to drive a stick shift. Seriously! It requires a little finesse to learn, but it really is like riding a bike: once you learn, it's instinct.

Automatic transmissions are preferred by many people who have longer commutes, especially if those commutes involve frequent congestion or a lot of stop signs/traffic signals. An automatic gives you an easier, less involved driving experience. Most larger vehicles - and increasingly, many smaller ones - can only be purchased with an automatic transmission in the US.

However, automatics can bring complications as well, especially on older cars. Most automatic transmissions need to have their fluid flushed and refilled every 15,000 miles, and I've found that owners can be negligent about this. Automatics also rely on an intricate series of switches and cables to help the car's computer decide when to shift, and if these components fall out of adjustment, it can result in the car shifting at the wrong time or being sluggish to upshift or downshift.

I tend to prefer manual transmissions for several reasons. They:

The primary downside to a manual transmission is the clutch. If the previous owner was not particularly skilled in clutch operation, premature clutch wear can take place. I've seen it happen as early as 75,000 miles. Replacement of the clutch is a major investment that should be planned for at around 150,000 - 200,000 miles on average. Individual brands can of course be better or worse; my GTI's original factory clutch doesn't slip at all at 163,000 miles.

However, many manual transmissions are sealed ("maintenance-free") units that do not require draining and refilling. They also have fewer parts than automatics and therefore break less often.

Vehicles with automatic transmissions are the clear majority in the United States and thus will give you a much wider selection when shopping.

Ultimately, the transmission style you choose will depend on your personal preference.

Performance vs. Efficiency

Most people will say that they want a vehicle that is as cheap as they come to keep filled up with gas. There are three primary factors that determine fuel consumption:

Engines

Almost all cars on the road today use an internal combustion four-stroke Otto cycle piston engine. A piston engine uses a metal block with three to eight big holes in it (some exotic cars have more). The big holes, or cylinders, have pistons that fill up the holes. When you push down on a piston, it forces a shaft - the crankshaft - to turn. For each set of cylinders, you have another big metal block on top of them, the cylinder head, that seals up the whole chamber.

Through a complex series of physical interactions, valves in the cylinder head open to either let air and fuel into the cylinder, or eject burned exhaust gases out of the cylinder.

The four stroke cycle works as follows:

  1. Intake stroke (piston moving down): The intake valves open. The piston's downward motion causes a vacuum, so air from the intake is sucked into the engine. This air has already been mixed with gasoline by either a carburetor or an electronic fuel injection system - the latter on almost all modern cars.
  2. Compression stroke (piston moving up): The intake valves are closed. The cylinder is now sealed up, and with the piston moving upwards, the air and fuel are compressed.
  3. Power stroke (piston moving down): A spark plug at the top of the cylinder emits a spark which ignites the fuel. The fuel explodes, causing downward force to be exerted on the piston.
  4. Exhaust stroke (piston moving up): The exhaust valves open. The piston moves up in the cylinder, pushing the gases out through the exhaust side of the cylinder head and eventually out your muffler and tailpipe.

If you noticed, in a four stroke engine, each cylinder only spends 1/4 of its time producing power. The rest of the time is spent setting up the process or ejecting waste. This is why four-cylinder engines are the most popular choice for cars today: four cylinders is the minimum number you need for a more-or-less constant level of torque output. (In practice, 4-cylinder engines aren't completely even, but they're close.)

Now that you know what a cylinder is and what it does, let's go over cylinder configurations. A cylinder configuration tells you the number of cylinders an engine has and how they're arranged. A single letter is used to describe the engine's shape.

Most engines have either four, six or eight cylinders. An I4 or L4 engine, pronounced "inline four", has four cylinders in an inline configuration. A V8 engine has eight cylinders in a "V" shape. The most common cylinder configurations in use today are I4/L4, H4, I6/L6, V6, and V8.

In almost all cases, the fewer cylinders you have in your engine, the less fuel it burns, but the less power it produces as well.

Displacement is how much volume exists in all of the cylinders when you add them all up. If you moved a piston to the bottom of a cylinder and filled up the cylinder with water, your displacement is how much water you have in that cylinder times the number of cylinders you have. Displacement is usually measured in litres (L) or cubic inches (ci).

Bore and stroke are, respectively, the diameter and depth of a cylinder. Exact displacement can therefore be calculated as:

D = π(B/2)² ⋅ S ⋅ n

Where D is displacement, B is bore, S is stroke, and n is the number of cylinders.

Drivetrain configuration

Your engine is set up to make the front wheels or rear wheels turn, or all of them if you have all wheel drive (AWD).

Front wheel drive (FWD) is the most common on basic cars. It leaves all the complexity up front, and is much better for driving in poor conditions than rear wheel drive (RWD). This is because on a RWD car, if one wheel loses grip and the other is still gripped to the road, it can push the back of the car out front. By contrast, FWD means the car is being pulled forward, and loss of grip from one wheel will be much easier to control.

RWD is better for dry conditions because of weight transfer. Go to your fridge and get the milk out. Set the milk on a table or the floor, then move the jug forward. Notice how the milk shifts to the back of the jug as you move it forward? That's weight transfer. With greater weight on the rear wheels during acceleration, RWD cars will hold their grip much better as they accelerate.

AWD is the best of both worlds - you get the solid handling of FWD with the acceleration benefits of RWD. But be cautioned: distributing your engine's power to all four wheels requires an extra set of gears and shafts, and with each gear and shaft you lose some energy. An AWD car typically has an engine tuned to make a little more power to make up for what's lost in the AWD mechanical bits, which will cost you fuel efficiency.

Both of my hatchbacks are FWD. While I'd like to own an AWD car in the future, the GTI with Firestone Winterforce snow tires handles very well in the snow and I'd readily recommend it.

Keep in mind that AWD does not make you invincible. AWD will do a great job getting you rolling, but good brakes and good tires, mostly the latter in snowy weather, are what stop you. A manual transmission AWD car with snow tires will be the best equipped vehicle for control in the snow.

Forced induction

Remember how above I said that engines have to suck air in by moving the piston down in the cylinder? No? Well go back and read "Engines" above. Then continue this section.

Forced induction means that a fan of some sort spins at your intake, thereby working proactively to suck more air into the system. By cramming more air (and a proportionate increase in fuel) into the cylinder, you can increase the total energy that is exerted during that all-important power stroke.

A car that doesn't use any forced induction is termed "naturally aspirated" - that is, the natural motion of the piston is the only way air is moved into the cylinders. The vast majority of gas-saving older cars are naturally aspirated.

There are two primary methods of forced induction in use. A turbocharger (turbo) spins the fan using energy from the exhaust gas that gets pushed out of your engine. It sits right behind the exhaust side of the cylinder head, and the gases flowing out of the head spin a shaft that, in turn, spins a turbine connected to the intake side of the engine.

Superchargers are driven by the crankshaft of the engine as an accessory on the side of the motor, the same way your alternator and air conditioning work. The rotational motion of the engine, as opposed to the exhaust gas, spins the supercharger's turbine, but the result is largely the same.

Superchargers feel more even as you're accelerating, as the engine RPM is directly proportional to the supercharger's turbine speed. Turbochargers have a critical point where the airflow increases dramatically and the acceleration becomes very strong. In either case, cars using forced induction tend to be either slightly or dramatically faster than their naturally aspirated counterparts, depending on the threshold at which the computer starts venting the pressure from the turbo or supercharger. Car enthusiasts commonly tune their engines to allow much higher pressures to be produced from turbochargers.

Generally, a car using forced induction, especially with high pressure (boost), will be markedly less fuel efficient than a naturally aspirated car. My Mazdaspeed3, which is turbocharged, achieves 18 mpg in the city and 25 mpg on the highway. The naturally aspirated version, which is the same exact motor without the turbo, achieves 22mpg and 29mpg city and highway, respectively.

Do I need a fast car?

Unless your career depends on getting very important people where they need to be or quickly getting away from the crime scene, you probably don't have a true need for a fast car.

But there are situations when having a faster car is really nice. Here in Connecticut, we have some highways where there's a stop sign at the end of a ramp to get on a highway. You have to enter the highway from a standstill and reach 55mph (or more) as quickly as possible to match the flow of traffic. There is no merge lane.

A faster car also means you can make evasive maneuvers or pass a slow moving vehicle more quickly, which can be advantageous on two-lane back roads when you occasionally get grannies who drive 10mph under the speed limit.

But remember that a faster car, depending on its appearance, can also attract more attention from police. Faster cars are also less fuel efficient across the board, and can be more prone to mechanical problems. Also remember the old mantra: "it's more fun to drive a slow car fast, than to drive a fast car slow."

Reliability

A lot of factors go into what makes a vehicle reliable. If you're reading this page you are almost certainly looking for a used vehicle; that means any positive or negative original aspects of the car's reliability will be multiplied by the maintenance habits of every previous owner.

Basic maintenance

A lot of the items below will depend on the basic care and maintenance the car has had previously. If the car had oil changes at or below the manufacturer's recommended intervals, was kept in a garage, and was regularly inspected and any issues repaired before they became big, the vehicle will most certainly last longer.

By contrast, if the previous owner didn't garage the car, didn't keep up with maintenance intervals, or ignored warning signs, their laziness will be your misfortune.

Basic maintenance items that should be done on all cars include:

OBDII + the Check Engine Light

Every model-year 1996 and later car comes with a data port hidden somewhere in the driver's side footwell or center console that looks sort of like a giant VGA port. Onboard Diagnostics Version 2, or OBD-II, is the name of this standard data port, which provides a facility for tons of information about the health of the engine and sometimes other components.

Modern cars are wired out the ass with sensors and indicators and can tell you just about everything that is going on. OBD-II provides basic information such as calculated speed and engine RPM but will often also send more in-depth information. You can usually read the exact coolant temperature, air/fuel ratios (both commanded and measured), oil pressure, component status for self-tests and much more.

Perhaps the most important feature of OBD-II is its diagnostic codes. Chances are you've seen or heard of the "check engine" or "service engine soon" light. This indicator on the dash is scary to many new car owners because it's impossible to tell why it's on without an OBD-II tool.

Thankfully, OBD-II tools are cheap and widely available. You can buy a basic scan tool from your local auto parts store, but it's even cheaper and more effective to buy a Bluetooth adapter and install an app on your phone or tablet that communicates with the adapter. Android users can use Torque (free, with a $5 paid version) and iOS users can use Engine Link ($5.99).

Body and frame health

The frame is the portion of the car that everything else sits on. In modern cars, the frame is a very high strength steel designed for resilience in extreme crash scenarios.

If the frame gets heavily rusted or is damaged in an accident, the car should be sent to a junkyard. No ifs, ands or buts. A bent frame, even if only bent by a little, can seriously compromise safety of the car, introduce strange reliability issues, increase tire wear, and generally make your life suck. If a car has frame damage, don't buy it.

Engine, transmission and drivetrain

The biggest engine issues to look out for when evaluating a potential car are engine knock, misfires, oil issues, and belt maintenance.

There are three major types of engine knock: spark knock, rod knock and piston slap. Spark knock is usually on-and-off, and is the least serious of the three. It is caused by a spark plug failing to ignite, and fuel combusting automatically when cylinder pressure reaches the combustion threshold. It is common for it to occur on a cold start, and is almost always fixed by changing the spark plugs and wires (where applicable).

Make sure you get the correct type of spark plugs for your vehicle - copper, platinum and iridium plugs are all built and adjusted differently. Also ensure the manufacturer's recommended fuel octane rating is used in the car, and that you use a gap tool to correctly set the gap on your spark plugs when you replace them.

Rod knock and piston slap are both much more serious. Rod knock does not go away with acceleration and is typically much louder. It is caused by worn bearings between the connecting rods and crankshaft; it indicates a major problem with the engine and will require major work to repair. Piston slap is similar: it occurs when there is too much clearance between the piston rings and the cylinder wall. If a potential car exhibits either of these symptoms, walk away.

YouTube is short on good videos of engine knock, but this one is pretty accurate.

Make sure the heater works, even if you live in a warm environment. A malfunctioning heater indicates a possible coolant leak which can mean serious engine damage.

Misfires can be identified by a stuttering exhaust noise and, typically, the check engine light on or flashing. These are often caused by bad spark plugs as well. Require the previous owner to change the spark plugs and wires (if applicable), and if the misfire is still there, walk away.

Remove the oil dipstick and ensure that the oil flows freely and is not completely black (it can be a dark brownish color if it is close to needing a change). If there is any gunk or grime stuck to the dipstick, or if the oil is not filled between the MIN and MAX marks, walk away.

If you are looking at a vehicle with an automatic transmission, warm the vehicle up, put it in park on a level surface and then take the transmission fluid dipstick out with the engine running. Again, check that the fluid is generally clear and between the MIN and MAX lines.

Make sure the vehicle shifts at the right time, both under light driving and load. If you're mashing the throttle it should shift around 4,000-5,000RPM, and if not it should shift at 2000-3500RPM. Make sure the vehicle doesn't jerk around when shifted.

If the vehicle you are considering has a manual transmission, Google search to see if it has a maintenance free transmission. If not, check the dipstick.

Ensure that it shifts smoothly and that the gear shift engages all gears smoothly. Ensure that you can comfortably row through the gears (shift quickly through all gears in ascending order) while holding the clutch. Verify that the vehicle is not excessively slow to start and that the throttle does not jump around when you start from a stop; this may indicate clutch wear.

In front-wheel drive cars, the constant velocity (CV) joints can make quite the racket if they are going bad. If this is the case, there will be a grinding, clacking noise proportional to your speed.

Brakes, suspension and steering

Try to brake hard from 30mph to a stop once, and then try slowing to a stop with the brakes several times. The vehicle should perform as expected. Make a note of whether you feel a "bumping" response in the brake pedal when braking aggressively - this is ABS doing its work. If the car has no ABS, or the ABS doesn't work, make sure you understand what wheel lock feels like, and get some practice braking without ABS in a safe environment before you go out into the wild world.

Check that no particularly loud noises are made when you turn the wheel. Almost all vehicles have hydraulic or electric power steering, so turning the wheel, even when stopped, should be easy. Assess the amount of work required to keep the vehicle driving straight on a straight road; if it pulls to the left or right, check the tires for uneven wear and have the previous owner get an alignment before you buy the car.

Make sure no corner of the vehicle is sagging relative to the others, and make sure the height of the vehicle above the wheels looks normal, unless you know the car is lowered. (If the car was lowered, check that proper springs or a suspension kit was installed, and that the car isn't just running on cut springs!)

Check the tie rods by rapidly pumping the steering wheel back and forth with the vehicle stationary. If there is a knocking or clacking noise coming from the wheels, you may need to have the inner and/or outer tie rods replaced.

Electrical

Community support

This is an invisible and often-overlooked but extremely valuable aspect of vehicle maintenance. All vehicles will have their share of cryptic, hard-to-diagnose problems, but chances are whatever problems you have, someone else has experienced the same thing before.

There are a number of brands that have a large enthusiast crowd surrounding them. Volkswagen, Subaru and Jeep are the three communities that seem to be the most helpful and technically apt, with smaller/less helpful communities around many of the Japanese brands such as Mazda, Nissan, Honda and Toyota. BMW has a good community too but parts for BMWs are very expensive and maintenance is meticulous as compared to most cars. Every brand has some enthusiasts, of course, but the first three I've named above are generally the best and most welcoming.

I'll quickly cover resources and generational names used for each.

Volkswagen

Good VW resources include VWVortex, TDIClub, and /r/Volkswagen on Reddit.

VWs are referred to by generation: MkI, MkII, etc. (pronounced "mark one", "mark two", you get the deal). Roughly speaking, here are the generational breakdowns by model year in the United States:

Jeep

JeepForum is chock-full of really well written pictoral guides and comprehensive documentation of common Jeep problems.

Generations are referred to by the two letter code, usually ending in "J". ZJ is all Grand Cherokees from model year 1992 to 1998. There's a few others. Google it.

Subaru

Don't have experience here. Someone with a Subie can fill in.

Mazda

MazdaSpeedForums is the biggest online resource for Mazdas. Unfortunately, the people on there tend to be young kids who have no idea what they hell they're talking about, and so you should take advice from there with a grain of salt. The moderation staff is also evidently quite immature, and nags you for donations a lot.

MSF generational lingo mocks a Japanese accent by referring to recent Mazda model generations as "genwon" (generation 1), "genpu" (2) and "genpe" (3).

Winter agility

Handling

Customization potential

The buying process

Research

I've tried to include as much info on this page as possible to help you decide what you want. At minimum, decide on the following:

Are you replacing an existing car? There's an old mantra that goes, "the cheapest car is the one you already have." This is not always true, but in my experience, it is most of the time. If a bunch of things break on your car all at one time, and none of them involve internal engine damage, overheating or extensive electrical damage, it will probably be cheaper to fix the car and keep driving it than to replace it and start over with a whole new batch of problems.

Searching

Inspection

Inspect the car before you test drive it. This is for two reasons.

  1. Sometimes you become attached to the car when you drive it (yes, seriously)
  2. Some problems will only be evident if the car is started with a cold engine

... to be continued ...

Test drive

Negotiation

Final decision

Paperwork

Emissions test/Safety inspection

Bill of sale

Title

Insurance

Costs

Paying for the car

Insurance

Sales tax

Title and registration fees