I’m told I need to replace the engine coils to the tune of $300 each at the dealership.

Is an engine coil the same as an ignition coil? How much of a risk is there in having a non-dealership mechanic do this repair?

My car has 52000 miles.
My car has an automatic transmission.

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Replacing one coil might cure the misfire and codes for now, but the other coils could fall prey to the same failure and codes. Replacing all for the coils at a time will save a comeback. This is why some ignition coil manufacturers package coils in sets.
This is a OEM MINI Cooper Coil Pack for all Gen 1 MINI`s. This coil will fit all R50 and R52 MINI Cooper, and all R52 and R53 MINI Cooper S`s. We find the most prominent issue with the ignition coil on these cars is the #3 coil plug rusts causing misfires, accompanied by an illuminated check engine light.
You can replace one coil at a time or all at the same time. I would however recommend having all spark plugs replaced with the coils so you do not have to remove coils twice.
A good quality, branded aftermarket ignition coil should last at least as long as the genuine part that was fitted to the vehicle at the factory. Yet, low-quality replacement coils are entering the market, especially online.
Coil Replacement

Replacement coils must always be the same basic type as the original and have the same primary resistance as the original. Using the wrong coil may damage other ignition components or cause the new coil to fail.

Engine misfires can also be annoying. But before you take your car to the auto shop to see what`s wrong, check your ignition coils. Choosing the best ignition coil ensures you get the best efficiency out of your car, which means you spend less money at the pump.
The ignition coil is a device which is capable of generating a high voltage pulse which goes to the spark plug. Coil pack refers to the set of coils used in the engine which do not run a distributor. A computer controls the set of coils. Each coil will supply power to the individual spark plug or a set of spark plugs.
If you notice that your car is misfiring or stalling, it could be an indicator of a bad ignition coil. Other symptoms include rough idle, misfire during acceleration, and hard start. This part may stop working correctly if a vehicle has bad spark plugs or plug wires, or if there is an overload with the voltage.
A malfunctioning ignition coil will cause your vehicle to misfire when you accelerate. In extreme cases, a misfire could cause your vehicle to shut down while you are driving.
Aftermarket Ignition Coils Are Cheap In Every Sense

In general, aftermarket parts have an advantage over OEM parts: price. Aftermarket ignition coils can fit a variety of makes and models. That means aftermarket manufacturers can sell them to a bigger audience for a lower cost.

Ignition coil packs are manufactured in such a way that they could last the lifetime of the vehicle, but due to failure in the proper maintenance of your car can cause them to fail earlier. Generally, they fail between 120,000 to 150,000 miles or between 5 to 7 years.
At the end of the day, as long as you stick to Bosch, Eldor, or Delphi, your Bimmer will be fine. Any of these brands will get you the performance you need and ensure the long-term reliability of your engine.
Coil Size Matters

Why does that matter? Well, the larger you make the voice coil, the more power it can handle—but at the same time, it also generates more heat. Smaller coils can be a little more resonant, but larger coils tend to have better control. Some speakers have to have larger coils.

More windings and heavier gauge material for those windings typically improves the performance of a coil. Davis points out however that often even with those changes an upgraded coil can fit within an OEM size case or housing, or one that is only slightly larger.
Vehicles with bad ignition coils often run roughly. This means, when your vehicle is idling, you may notice a rough feel or sound. Your vehicle may also experience a drop in power. As a result, a bad ignition coil can make it acceleration more sluggish.
Oil damage is another cause of ignition coil repairs. If a customer comes in for parts relating to an oil leak, the spark plugs and ignition coils might also have been damaged and in need of replacement.
It`s important to remember that many times when a coil fails, it becomes weak. It still produces spark, and may still run the vehicle fine at times, but often under load, or acceleration, it can produce a misfire. Other times, the coil completely fails and stops working altogether.
What kills ignition coils is location; being mounted in one of the hottest, most vibration prone and dirtiest parts of the engine. Modern ignition coils are typically located between two camshafts on the valve cover and exposed to dirt and oil.
Keeping your spark plug in optimum condition can reduce your chances of experiencing an ignition coil failure. As spark plugs wear down, the gap in each spark plug is fired is widened meaning the coil needs to provide a higher voltage in order to bridge the gap.
All Bosch ignition coils are built to achieve or exceed OE specifications and are known industry-wide for their reliability and performance.
The ohmic resistance of the coil is around 0.2–3.0 Ω on the primary side and around 5–20 kΩ on the secondary side.
Ignition coils generally last 80,000 to 100,000 miles.
However, most coils, when selected correctly, and in systems that are properly maintained, can last anywhere from 10-30 years! 10-30 years is also a pretty wide range, and there are many variables in how long you can expect a coil to perform.
This brings us to the question of whether to get OEM or aftermarket ignition coils. Which type is the better investment? The answer is always, always OEM. Whether you have an Econoline or another model with ignition coil issues, OEM coils are always a great investment.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

Need to replace bad spark plug & coil pack on Ford Expedition but not sure what else I need besides the plug and coil pack?
ANSWER : Hi There,
I would recommend having an expert from YourMechanic come to your location to take a look at the vehicle to first determine what the cause of the misfire is if this has not already been done. Engine misfires can be caused by many different problems and are generally caused by either a spark or fuel issue or in some cases, a combination of both. Spark related problems generally will result from things like ignition coils, crankshaft position sensor, spark plugs, spark plug wires or ignition modules not working properly. When the misfire results from a fuel related issue, this is commonly related to a lean fuel condition (lack of sufficient fuel supply to the motor). Fuel related misfires can be caused by many different things such as low fuel pressure, faulty or dirty fuel injectors, a faulty O2 sensor, a dirty or failing mass air-flow sensor, a faulty or dirty idle air control valve or a vacuum or intake leak. When the fuel supplied to the combustion chamber is insufficient, this results in an ignition (spark) that is igniting a less than balanced load of fuel and air. This results in a misfire or an explosion in the cylinder that is much less powerful than the other cylinders. This creates a loss of power that resonates throughout the motor additionally causing other problems with ignition and fuel timing. Due to the number of different things that may cause an engine misfire, the quickest and easiest way to diagnose this type of problem is to hook the vehicle up to a scanning tool which will download any potential fault codes that may have registered in the vehicle’s computer as a result of the poor running condition. I would recommend having an expert from YourMechanic come to your location to diagnose your misfiring problem.

I have a 2010 camry. I just recently replaced the engine with a 2014 camry engine. Now I have Four engine lights on. I replaced on
ANSWER : If you swapped the engine from a vehicle that is 4 years newer than the car is then you are going to have electrical and sensor incompatibilities that may not be able to be fixed by just a few sensor replacements. There were many changes in computer and emission related items between 2010 and 2014 engines. I would recommend having a mechanic like one from YourMechanic come to you and compare the two engines to isolate the possible differences and see if the problem can be fixed.

Hey Allen. I just rebuilt (?) the engine on my 06 Acura TL. Now the engine line went on. They told me the engine? can blow up if I
ANSWER : Hi there. I think it may be a good idea to find a new mechanic. Fortunately, our mobile mechanics are able to complete most diagnostic inspections and complete a lot of repairs services at your location, and on your schedule. In what you are describing above, the current issue seems to be with your EVAP system, which is designed to relieve pressure in the fuel tank and also collect harmful vapors before they escape into the air. Now, in regards to the car "blowing up"; that’s a bit dramatic, but it is important to have your issues repaired if it’s related to the EVAP system. Here is what I would recommend. Set up an appointment to have one of our mobile mechanics come to your location to complete a check engine light inspection – (click here to set up an appointment). This will allow them to download the stored error codes that cause the light to illuminate and determine what parts need repair or replacement. Then, they’ll be better prepared to provide you with a repair estimate and complete the repairs in most cases for you.

How many ignition coils do I need for a 2006 Lincoln zephyr?
ANSWER : Your vehicle has a 3.0 liter engine and has a coil per cylinder. You have a 6 cylinder engine and have 6 coils. You do not need to replace the engine computer.

Do i need to replace the receiver drier and/or the expansion valve when replacing the condenser assembly?
ANSWER : Replacing the system drier is absolutely essential. If the system has been open to the atmosphere (due to the leak in the condenser), the desiccant in the drier has been fully saturated with moisture. As far as the expansion valve, replacement is not normally implicated in a leak repair, in your case a leak in the condenser. To justify replacing the expansion valve, there would have to have been a diagnostic performed which proved a fault. If no diagnostic was performed, and there is no evidence of a fault, then it is pointless to replace the valve. But, again, drier replacement is absolutely essential. To add the drier to your order, you can simply add a note to the mechanic in your order and/or add it as a service (you will see a link that you can click on to "add services" or write in specific services). If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

Engine swap details needed. I need to know if the swap will fit.
ANSWER : Hi there. When it comes to swapping engines for your vehicle, what you can do is check all of the engine mounts and transmission mounts and make sure that they will work. If the mounts are a little off but there is room, then you may have to retro fit a custom mount. Check the length of the engine and the transmission assembly together. Make sure that the assembly is the same length. It may be okay if it’s a few inches shorter or longer, however, it cannot exceed 3 inches or the assembly will not fit. There has to be room for the engine to move around. Also, keep in mind, the CV shafts may not match up to the transmission and wheel hubs, especially if the transmission is shorter or longer. If you need further assistance with swapping your engine with another engine, then seek out a professional, such as one from Your Mechanic, to help you.

Does the replacement of a thermostat include replacing the housing? I was told I needed to replace the thermostat housing.
ANSWER : Hi, thanks for writing in. The thermostat housing and the thermostat itself are two different components and do not necessarily need to be replaced together or at the same time. The housing is just a piece that covers the thermostat that also has an opening for a radiator hose which is where the water enters and exits the motor. The housing may need to be replaced at times if it is cracked or leaks severely, however they are indeed two different and distinct pieces.

Hope this helps and best of luck.

The engine klunking and tapping, needs engine replacemet
ANSWER : The reason the shops told you to replace the engine is that they do not overhaul engines. They can only replace it for you with a remanufactured or used engine. An overhaul is a third option but would most likely not be as cost effective and may even cost you more since the labor and parts can be more than replacing it. Since you already had two shops say it needs an engine, then I would suggest having them both give you quotes on remanufactured or used one. Make sure to get the warranty in writing so you can see if a future failure is covered.