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Discussion Starter · #1 ·
I just bought a 2012 500c Pop with 106000 miles. I’ve owned it less than a month I think it’s DOA.

I was driving it today and the check engine light starting flashing(I know this usually means a misfire) I managed to get it 2 blocks from my house and it died.

I tried restarting after I pulled it over and nothing. I pulled the spark plugs and #1 ignition coil was broken in half and smelled /looked burnt. I pulled the spark plug and the electrode was pressed against the resistor. I bought a new plug and coil and put them in and nothing. I checked the plug for spark while a friend turned the key and I didn’t see anything.

I guess I’ll do a compression test tomorrow, but I fear this engine is DOA. If compression is ok, what should I check next that could cause no spark at the plug? Thanks in advance and it really stinks to have this happen, the car was fun to drive.
 

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No spark and compression have nothing to do with each other, so you may be in luck, it may just be some electrical thing, not the major engine internal issue. I'm assuming it turns over, right? Might as well check compression, but you need to find out why it doesn't have ignition. Swap the coil with another cylinder and test to make sure that the replacement coil is properly working.
 

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Discussion Starter · #3 ·
No spark and compression have nothing to do with each other, so you may be in luck, it may just be some electrical thing, not the major engine internal issue. I'm assuming it turns over, right? Might as well check compression, but you need to find out why it doesn't have ignition. Swap the coil with another cylinder and test to make sure that the replacement coil is properly working.
No spark and compression have nothing to do with each other, so you may be in luck, it may just be some electrical thing, not the major engine internal issue. I'm assuming it turns over, right? Might as well check compression, but you need to find out why it doesn't have ignition. Swap the coil with another cylinder and test to make sure that the replacement coil is properly working.
I wanted to check compression because something obviously bad happened in that cylinder. The plug was black and the coil was burned/broken in half. But I have no spark to any of the plugs. What could cause the lack of spark going to the coils?
 

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So the engine cranks, but no spark on any of the coils, correct? That could indicate a lot of things. As you know, the way coil packs work it's controlled directly by the ECU, right?, based on the various parameters sent via bunch of different sensors. I can't remember right off top of my head right now which one but there's a fuse box in the engine compartment, you may want to check the one that runs the ignition. Also often suspect is crank position sensor - that's definitely one sensor that controls the spark. I don't know how it could be possible for the coil pack to break in half, but that might just be a red herring (maybe the broken coil pack is not a symptom, but a cause), I just can't think of any condition that could cause the coil pack to physically break in half.
 

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Discussion Starter · #5 ·
i have a code reader coming today, could the cam position sensor do it too? I’m going to check the fuses and clean the cam sensor and see if that helps. Thanks so much for your help with this.
 

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Yeah, camshaft position sensor can 'ultimately' cause that, too, it's part of the parameter. My inclination is from the fuse, then crank position sensor, then other sensors. Complete loss of spark on the individual coil pack is just a bit baffling, so it must be caused by something like fuse or some sensors. It's unlikely the ECU is bad, but you can't write off that possibility just yet. By the way, this does not always apply, but I've had such a mixed experience with aftermarket sensors, particularly on Mopar cars, so it may be the best if you go with OEM parts on those.
 

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Discussion Starter · #7 ·
The car was misfiring pretty badly before this happened. So maybe one of those sensors was bad?
 

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Wow...I wasn't expecting that at all. There's something really peculiar about the way everything looks there. Like the thread of the plug has the same sort of soot as well as the rest, which is very strange. Also the gap - the electrodes are touching, as if it was pushed together, but not like piston kissed it or anything. I don't know what you find, but I'm very interested to hear about the rest of the story.
 

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Discussion Starter · #13 ·
The car was misfiring badly just before it stalled and wouldn’t start again after I pulled over. I just cleaned the cam sensor and replaced the plug and coil and the car has no spark. I’m waiting for a code reader and I’ll share what I find once I look into it. Thanks
 

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I notice too, there is no plug gap. Very strange. The electrode is welded to the contract.
I personally can’t see how that engine could run.

109923
 

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Discussion Starter · #15 ·
I notice too, there is no plug gap. Very strange. The electrode is welded to the contract.
I personally can’t see how that engine could run.

View attachment 109923
This plug was gapped prior to this event. Something pushed the electrode into this position. I have no idea what exactly, but there was obviously a major detonation in this cylinder
 

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I wonder what happened. The plug and coil looks completely charred, like it got really really hot, hot enough to char the whole **** thing, and melt the coil. That codes are all electrical - like there's a catastrophic electrical short somewhere between injector/coil and ECU, or something like that. I think you should check the compression just to confirm that the engine physically okay. If there's any internal damage, there's no point in troubleshooting this. If the engine is healthy, then the fun begins. I'm trying, but I don't think I've seen one quite like this before.
 

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Discussion Starter · #18 ·
I appreciate all your help, I guess next I’ll compression since I think something really bad happened in cylinder 1. I just spent 3500 on this car and have owned it less than a month, this really stings.
 

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Any chance the alternator is bad and was causing this?
Man, I'm sorry man...
You mean, like overloading? It probably won't, because the first thing in that case would be regulator/rectifier, and that would be distinct. I'm crossing the fingers that engine is physically okay! I just can't imagine what in the engine can cause such a extreme condition that affects the spark plug and the coil. I'm still betting my fiver that engine is okay... Speaking of which, when you try to crank, does it turn over? Do you hear any banging, or other abnormal noise?
 
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