Mobile Tune-Up in Columbia, SC

What Is a Tune-Up on a Modern Car?

On most cars today, a tune-up means new spark plugs, plus a check of the ignition coils and the air filter. Older cars had parts that needed adjusting, like points and a carburetor. Modern engines are run by a computer, so there’s little left to adjust. What still wears out are the spark plugs and, in time, the coils.

So when you call for a “mobile tune-up,” tell us what the car is doing. Your mechanic will check the engine and replace what’s actually worn.

What Are the Signs You Need Spark Plugs or Ignition Coils?

• Rough idle: the car shakes or shudders at a stop light.
• Misfire: a stumble or jerk when you speed up, like merging onto I-26.
• Check engine light: steady or flashing. Misfire codes start with P030.
• Worse gas mileage than the car used to get.
• Hard starting, or the engine stalls.
• Loss of power going up hills or when the car is loaded.

These signs can also come from fuel, air or sensor problems. That’s why the engine gets checked before parts get replaced.

Is It My Spark Plugs or an Ignition Coil?

It takes a test to know. Each cylinder has a spark plug. On most modern engines, each plug also has its own ignition coil sitting right on top of it. The coil makes the high voltage, and the plug makes the spark.

Here’s how a mechanic tells them apart:

1. Read the codes. P0300 means random misfires. P0301 to P0308 point to one cylinder: P0301 is cylinder 1, P0302 is cylinder 2, and so on.
2. Swap the coil. The mechanic moves the coil from the bad cylinder to a good one. If the misfire moves with it, the coil is bad.
3. Look at the plug. A worn, cracked or oil-soaked plug shows it needs replacing.

If the misfire doesn’t follow the coil or the plug, the cause may be a fuel injector or a mechanical problem. Your mechanic will tell you before any more work is done. Learn more about check engine light diagnosis.

How Often Should Spark Plugs Be Changed?

It depends on the type of plug:

Most newer cars come with platinum or iridium plugs. Your owner’s manual gives the exact mileage for your engine. If you don’t know when the plugs were last changed and the car has high miles, it’s worth a check.

What Does a Tune-Up Cost?

Spark plug replacement typically runs about $150–$450, parts and labor. One ignition coil typically runs about $140–$350 installed. Your price depends on the engine. A 4-cylinder with easy-to-reach plugs costs less. A V6 or V8 with hard-to-reach plugs costs more, and some can cost more than this range. You get the price before work starts.

Typical ranges from public price guides; prices last checked October 2026. Ask about any trip or service-call fee when you call. See more prices in our mobile mechanic cost guide.

Can I Drive With a Misfire?

It depends on the check engine light:

• Flashing light: stop driving as soon as it’s safe. A flashing light means a serious misfire. Unburned fuel can overheat and damage the catalytic converter, which is a costly repair.
• Steady light with a slight shake: you can usually drive carefully for a short time. Get it checked soon, before a small problem gets bigger.

Here is more on whether it’s safe to drive with the check engine light on.

Can a Mobile Mechanic Do a Tune-Up at My Home?

Yes, in most cases. On many 4-cylinder engines, the plugs and coils sit right on top and are easy to reach. The job can be done in your driveway or a parking lot.

Some V6 engines are harder. The rear plugs can sit under the intake manifold, a large part that has to come off first. That takes more time and costs more. Ask when you call if your engine is one of these.

Diesel trucks don’t have spark plugs. For a diesel that’s hard to start, see mobile diesel truck repair.

Should I Replace All the Ignition Coils at Once?

Not always. A coil that tests weak, is cracked or is soaked in oil needs replacing. If the coils are hard to reach or the car has high miles, replacing them all with the plugs can save a second job later. Spark plugs are different: they are usually replaced as a full set, so every cylinder fires the same. Your mechanic will explain what your car needs and what can wait.