A misfire is one of the most common reasons a German car turns on its check engine light. Most of the time the cause is an ignition coil or a worn spark plug. Just German Automotive replaces ignition coils and spark plugs on Audi, BMW, MINI, Mercedes-Benz, Porsche and Volkswagen in Tampa, FL, and we find the actual failing cylinder before replacing anything, so you are not paying to swap parts until the problem goes away.
Signs of a Bad Ignition Coil or Spark Plug
- A check engine light, especially a flashing one
- Rough idle or shaking at a stop
- Hesitation, stumbling or a loss of power when accelerating
- Worse fuel economy than usual
- A car that feels fine when cold and misfires when warm, or the reverse
A flashing check engine light means a severe misfire. Unburned fuel can overheat and damage the catalytic converter, so reduce speed and have the car checked as soon as you can.
Why German Engines Are Hard on Coils and Plugs
Most modern Audi, BMW, Mercedes-Benz, Porsche and Volkswagen engines are turbocharged and direct-injected. High cylinder pressure makes the spark plug work harder, and the coil sits right on top of a hot engine. As plugs wear, the gap grows and the coil has to push more voltage, which is one reason coils fail. Many turbocharged German engines call for spark plugs sooner than older engines did, so check your maintenance schedule rather than assuming plugs last 100,000 miles.
Oil in the spark plug wells, often from a leaking valve cover gasket, can also cause misfires. If we find oil there, we will show you, and our oil leak repair page explains the fix.
How We Diagnose a Misfire
We read the fault codes and the live misfire data for each cylinder with a scan tool, then confirm the cause. Swapping a coil to another cylinder and watching whether the misfire follows it is a quick way to tell a bad coil from a bad plug or injector. We check the plugs for wear and for signs of oil, fuel or overheating, which tell us about the health of the engine.
Not every misfire is ignition. Vacuum leaks, injectors, carbon build-up and timing problems can all cause one, and if the cause is not obvious our diagnostics and programming work picks it up from there.
One Coil or All of Them?
If a single coil has failed and the others test fine, replacing only the bad one is a fair option, and we will tell you so. If the plugs are due and the coils are original on a high-mileage engine, doing them together can save a second visit. We lay out both options with photos from our digital vehicle inspection, and every coil and plug job is covered by our 3 years / 36,000 miles nationwide warranty.
What Affects the Cost
- Number of cylinders: four, six or eight
- Spark plug access, since rear plugs on some V6 and V8 engines need the intake removed
- Whether one coil has failed or the coils and plugs are due together
We quote each car individually, and you approve the quote before any work starts. If you have an estimate from another shop or a dealership, we offer a free second opinion.
What Customers Say
“I even had spark plug replacement as something I thought I needed but they called me while doing service and told me they were not going to replace as they were still good.”
We work on Audi, BMW and MINI, Mercedes-Benz, Porsche and Volkswagen.
Related Reading
Frequently Asked Questions
Can I drive with a misfire?
With a steady check engine light and a mild misfire, driving gently to the shop is usually fine. With a flashing check engine light, reduce speed and get it checked right away, because a severe misfire can damage the catalytic converter.
How often should spark plugs be replaced on a German car?
It depends on the engine. Many turbocharged Audi, BMW, Mercedes-Benz, Porsche and Volkswagen engines call for spark plugs sooner than older engines. Your maintenance schedule or your car's service display gives the interval, and we can look it up for you.
Should I replace all the ignition coils at once?
Not necessarily. If one coil has failed and the rest test fine, replacing just the bad one is reasonable. On a high-mileage engine with original coils, replacing them together can prevent the next one failing soon after.
Spark Plug and Ignition Coil Replacement Near Me
Searching for spark plug replacement near me or ignition coil replacement near me in Tampa? Just German Automotive is at 4411 N Lois Ave, Tampa, FL 33614, open Monday to Friday, 8:00am to 5:00pm. We are in Drew Park on N Lois Ave, about half a mile from Dale Mabry Highway, close to Raymond James Stadium and a few minutes from Tampa International Airport.