Disconnect the wiring from the ignition coil for cylinder number one while the car is still moving, and then pay attention to the idle sound for any changes. You can tell that cylinder number one was the issue if there isn’t an audible difference in the sound. You can tell it was a cylinder other than number one if there was a discernible change in the sound or how the engine ran. If so, proceed further up the line until you locate the problematic cylinder.
In This Article...
Step 5
Look at the coil’s tip where it connects to the spark plug. Three interactions are planned. The two on the outer serve as the main connections. Check the contacts using an electric ohmmeter. To determine how many ohms the coils are producing on the readout, place the ends of the ohmmeter testing wires on the contacts. The allowable range, according to BMW, is between 0.4 and 0.8 ohms.
SERPRESULT
An ignition spark tester, such as OEM 25069, replaces a spark plug, is grounded to the engine, and may quickly demonstrate whether a specific wire or coil is malfunctioning.
Boostist
The vast majority of automobile coils may be tested using this method. Check the resistance between the coil’s side terminals with an ohmmeter. Disconnect all of the coil’s wires before performing this. Resistance should range from 0.75 to 0.81 ohm. Then measure the resistance between the central high tension terminal and either side terminal. It should read between 10,000 and 11,000 ohms. Any considerable departure from these values would suggest a problem with the coil.
Symptoms of Ignition Coil Failure
The main sign that there is a problem is when the ignition coil starts to show symptoms of failure. You can more precisely focus your suspicions if you are aware of the symptoms linked to ignition coil issues.
Inefficient fuel use and poor gas mileage
Your ignition coil is one of several potential causes for why your BMW may not be getting as many miles per gallon as it formerly did. This is a result of your engine’s systems attempting to make up for the broken component.
Misfires in the ignition and stalling
As we’ve learnt, your ignition coil plays a key role in ensuring that the spark plugs can ignite the engine’s fuel. As a result, if the coil has acquired flaws, ignition may be difficult to achieve or may not occur at all, increasing the possibility of misfires or stalling.
A Fight to Start
Similar to the previous point, you might have noticed that your BMW takes a few tries to start the engine and doesn’t start the first time. To avoid the coils unexpectedly falling completely and leaving you stuck, this should be taken seriously and resolved right away.
Heating-Up Engine
Overheating is one of the main reasons why engines fail too soon. Therefore, you may need to check your coil for damage if you’ve experienced recent overheating issues or noticed temperature spikes inside your engine.
Engine tremors
A loud, juddering engine is an obvious indication that there is a problem with the engine system. The ignition coils may have further problems as a result of vibrations harming their fragile internal components.
Spiking Plugs
Because they are directly connected to the ignition coil, if the spark plugs malfunction, your ignition coil may also malfunction as a result.
How do you use a multimeter to test an ignition coil?
Using a digital multimeter is another method for testing an automobile’s ignition coil. It is recommended to refer to your manual, which should provide the correct coil resistance reading, before opening the hood of your automobile. Under the hood, find the coil. Usually, one or a few bolts keep it in place. Disconnect the wiring harness.
The primary and secondary circuits in ignition coils need to be checked. To obtain a primary circuit reading, connect the multimeter to the negative and positive terminals of the ignition coil.
The ignition coil needs to be replaced if the multimeter displays a reading of zero ohms. The ignition coil needs to be replaced if the multimeter reading is higher than the range specified in the owner’s handbook.
Connect the multimeter’s positive pin to the positive terminal in order to test the secondary circuit of the ignition coil. Additionally, connect the multimeter to the spark plug’s high output terminal.
The expected electrical output from the spark plugs should again be found in the car’s manual, although a general range is between 6,000 and 10,000 ohms. Similar to the primary circuit, an ignition coil issue is indicated by a reading outside of the intended range. Once the ignition coil (or coils) have been inspected, swap out any that are defective and give your car a test drive to make sure everything is operating as it should.
Ignition coil testing equipment is available?
You can also unplug the coil, plug it back in, and use an ignition spark tester like OEM 25069 to check if the coil is firing if you think it could be dead. A multimeter can also be used to measure resistance.
How can I tell if the coil pack in my BMW is damaged?
You may have come to this page to learn more about these symptoms because you have already observed one or more of them. Regardless matter whether you have yet to suffer ignition coil failure, you should always be aware of the signs. The following are warning indications of a failed ignition coil:
- Misfire in a cylinder. The spark that passes through your spark plugs is generated by the ignition coil. Depending on how badly the coil is damaged, there may be no spark at all or untimed sparks.
- Power Deficit Your engine’s rhythm is thrown off if one or more cylinders fire at the wrong time or not at all. When the coil is defective, your BMW experiences performance problems as a result. Every cylinder is timed to fire once each rotation at a specific moment. Your engine’s efficiency is significantly impacted by one cylinder firing out of phase.
- Rushed Idling Your engine will tremor wildly when idling for the same reason that power is lost. This occurs because the cylinders that are working compensate for the failure of one or more cylinders to drive the spinning of your crankshaft.
- lower fuel efficiency Are you making more frequent trips to the gas station? Most likely the problem is with your ignition coil. The combustion reaction in one of your cylinders is not adequately sparked by a malfunctioning ignition coil. The cylinders that are still working compensate for the malfunctioning cylinder or cylinders by burning a lot more gas than your car should.
- The engine stalls. Your automobile will stall down unexpectedly as a result of misfires and power loss, and the engine may even completely shut off. Your engine will lose the momentum that propels it with just one poor rotation. Your engine won’t start, so you’ll need to start it again or risk getting stuck somewhere.
- Starting Issues A spark is required to ignite the cylinders and start the engine of your car. No spark results in no combustion in the cylinder and a non-starting engine.
- Check Engine indicator. A malfunctioning ignition coil that results in a misfire will undoubtedly alert your BMW’s computer to an issue with the engine. A code reader will identify the precise cylinder that needs repair.
Which ignition coil manufacturer does BMW use?
I understand that the replacement ignition coils for my 2010 BMW 325i have the part number BMW 12138616153. Delphi is the default brand that BMW supplies.
Would you purchase a Delphi or even a Bosch if you needed to replace all six?
Is there a different, more effective brand that is suggested for Australia?
I think the ones in my car (I believe they are Delphi) need to be replaced and I’m happy to replace them myself because it seems like a very straightforward task.
I recently acquired a Brimmerlife wiring harness from Vader Solutions in the United States, and I’ll be using red top hat coils from an Audi R8. Much better choice.
For my 325i, I literally just got some Delphi Coils from FCP Euro—they were the most affordable I could find. BMW rebrands them and charges twice as much for them.
Here is a post by DR-JEKL that discusses the various coil kinds in great detail:
Quote:
Most automobile coils and plugs have a lifespan of 100–200 thousand kilometers! The N54 is a high-performance engine, and adding a tune puts a lot more demand on the ignition system (and fueling system as well) to supply the gasoline and ignition to produce that extra power. If there is a weak link, the car will immediately enter limp mode (feels like you hit a brick wall – and you get the CEL check engine light)
These cars have terrible coil setups, and it’s not unusual for folks to get misfires even with coils that have been in use for 20–30k kays. Unfortunately, all you can do is trash them. The design of the coils, which sit in the engine recess and are subject to thermal radiation from the motor when the N54/N55 runs hot, is mostly to blame for this.
To try and prevent the coil from deterioration, BMW switched some engines from Bosch coils to Delphi, which has a metal sleeve as an insulator:
$270, freight included. Due to cylinder 6’s misfiring, I’m replacing it and haven’t driven for almost a week. Bosch coils are now fitted in the car; maybe, the Delphi version will have a little bit more life. In my perspective, there shouldn’t be a need to replace if the car is operating normally. 92,000 kilometers have been put on my automobile.
Are the ignition coils on all BMWs the same?
Even though some part numbers are for particular models, you can follow their origins. Consequently, every BMW ignition coil application from 2003 to 2016 is equivalent, if not interchangeable.
What is the lifespan of a BMW ignition coil?
- engine stalls
- erratic idle
- power outage
- lower fuel efficiency
- In rare instances stalling
- check-engine indicator
- Vehicle won’t start
Usually, ignoring these symptoms only makes things more annoying. Whether that just entails consuming more petrol than normal or getting parked in a parking lot because your car won’t start.
BMW ignition coils have a maximum service life of 140 000 miles. They are often only replaced when there are warning indicators of failure and not as routine maintenance.
What damages the coils in a BMW?
The heat and vibration from your engine can eventually lead to an ignition coil failure. Although insulated, persistent vibration and heat will eventually harm any electronic component. The telltale indicators of malfunctioning ignition coils can be identified by a qualified BMW mechanic.
Overvoltage from a defective spark plug or plug wire reaching the coil is the most frequent cause of ignition coil failure. Either will severely shorten the ignition coil’s lifespan. Bad spark plugs and wires can be avoided because your BMW’s instructions call for precise intervals between changes. Later costs will increase if plugs and cables are not replaced on a regular basis.
What signs might point to a failed ignition coil?
- losing power One of the initial signs of an ignition coil failure is this.
- Ongoing check engine light.
- Low fuel efficiency.
- Backfiring.
- Engine Misfire.
- Stalled and hard starts.
- Sounds of coughing and spluttering.
- Vibrating and Jerking
Should I swap out my BMW’s ignition coils all at once?
Coil packs are dependable and should endure for the entire life of the car. There is no need to replace everyone if one of them behaves badly. However, you should replace them all if one pack begins to malfunction after the odometer has traveled about 75,000 miles.
How frequently should coil packs be changed? They don’t need to be changed until symptoms start to appear. Most of the time, they don’t need servicing until they’ve traveled 120,000 to 150,000 miles.