What could be frying an ignition coil on a 2013 5.0i

[blaubenz]

I have an 2012 e70 5.0i. This is what is happening. It is getting a check engine light. Pull the code and it gets a P0301. Turbo not not kicking in (tell me if that is normal if I have the check engine in please). So I reset code old faction way disconnect battery. Start engine check engine came back within a min or 2 after restart.



So I changed the coil everything work good for about a day drive to work no problem 10 miles check engine light came back on coming home.



Something fried the coil. What would fry a coil. What could it be what do I check next?

[ard]

Lol

1. 'The old fashioned way'???? That doesn't reset the code.

2. Is that the sum total of diagnostic info on which you have determined the coil is 'fried'?????

3. Coils fail, you replace them.

4. But lots of things besides a bad coil can cause a generic P misfire code...

5. Bad coil and/or a miss in Cyl 4 will **NOT** cause the turbo not to kick in.

6. Maybe a BMW-specific code reader would be useful...ya think?

[blaubenz]

Originally Posted by ard

Lol

1. 'The old fashioned way'???? That doesn't reset the code.

2. Is that the sum total of diagnostic info on which you have determined ther coil is 'fried'?????

3. Coils fail, you replace them.

4. But lots of things besides a bad coil can cause a generic P code...

5. Bad coil and/or a miss in Cyl 4 will **NOT** cause the turbo not to kick in.

6. Maybe a BMW-specific code reader would be useful...ya think?

In reply

The reason I say something is frying #4 coil and the reason I ask what could be frying a coil is. I took the new coil just installed in bmw x5 5.0 that cleared the code and check engine light for a day put it in another bmw that was fine and the "new" coil caused it to through out the same miss fired code.


Goes back to what could be causing this car to fryed coils. What could I be looking for.



Also regarding the turbo. If the the bad coil cause a missfire would that put the car in a limp mode and cut off the turbo? Does a missfire code generally cut power to the engine?

[ard]

Originally Posted by blaubenz

In reply

The reason I say something is frying #4 coil and the reason I ask what could be frying a coil is. I took the new coil just installed in bmw x5 5.0 that cleared the code and check engine light for a day put it in another bmw that was fine and the "new" coil caused it to through out the same miss fired code.


Goes back to what could be causing this car to fryed coils. What could I be looking for.



Also regarding the turbo. If the the bad coil cause a missfire would that put the car in a limp mode and cut off the turbo? Does a missfire code generally cut power to the engine?

Here you go.... you are saying the motor keeps frying coils.


Try this on: it isnt the coil that is causing the misfire (!!!!)


If you make the assumption 'it isnt the coil", then would that not fit precisely what you have observed?








misfire codes DO NOT cut boost...do not (necessarily) cut power to the motor.

[ard]

I'll re-iterate the suggestion to buy a proper BMW code reader. Dropping by a shop for a read, then shotgunning borrowed replacement parts is so ghetto.

[crystalworks]

^ What he said. With any post 2001 BMW (varies by chassis, but generally 2001) you are going to need a code reader that can give you the specific BMW trouble code. A generic P-code is not going to do the job unfortunately. I use, and suggest, the Foxwell NT520 Pro. It's about $150. Can do 95% of anything even a tech would need.

A generic misfire code isn't going to help a bunch with diagnosing the issue. On that cylinder it could be the coil, plug, injector, carbon coked valve, worn cam lobe, etc. Some of those failures are more common than others, but as Ard was hinting at, shotgunning parts is not the best approach usually.