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So I haven***8217;t actually changed the ignition coil or pack since as of now I am not sure which it is. After browsing everyone has said there is only one single coil that I would need to replace since it s not a coil on plug system. Would that be correct? And if possible could someone link me a proper one that I would need to purchase?
 

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Transplanted JrzyBoy
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226 Posts
Boy, I could write a book on these

You have 6 coils for you ignition system. I am speaking of my 1991 E34 525i. Inline, from motor to firewall. Access the coils by removing 2-10mm nuts under the circular plastic escutcheons hiding them with a thin bladed screwdriver. These are prone to breaking from brittleness. You have to remove the oil cap to remove the plastic cover that says "BMW". Of note, the cover has up to 4 soft rubber-like dampeners, black in color, about an inch long that usually fall off--and a dab of RTV sealant is helpful to hold them in place. Most of these fall off and discarded, so it's not a big deal. Just providing that tidbit in case you find them and have no idea where they go. They are on the long side of the lip of the plastic cover-two top and two bottom. Once removed, replace the cap so you don't accidentally drop a bolt or anything else down there. Each coil is held on with 2 10mm nuts. Three of the coils have a copper braided ground wire, I believe it's numbers 3 and 6. Don't forget to put them back on when you replace them. The coils are easily removed by prying up on the retaining clips for the wires, usually with a short, flat screwdriver. Do this GENTLY, as the plastic gets brittle. I usually unclip the not-too-flexible black wiring that connects the coil and with some wiggling, off they come. Hard to rewire them back on incorrectly, so that's a plus. Remove all the nuts and lift up Simple. INSPECT THE COILS CLOSELY for damage. I just did work on mine and ultimately had three coils defective. One was arcing and you could see a burn mark on the gold engine head where the arcing took place. A second one had a hairline crack, and if I can find a picture, I'll post it. And the third...ah, the third. Had absolutely NOT OUTWARD DEFECTS, and it passed a bench electrical test...but under load...intermittent shorting. I just found that one yesterday. Replace it with a spare and the car purrs like a kitten. If the picture posts, the hairline crack should be visible. Not sure if it was defective, but BMW certainly didn't put it there, so I replace it. Good luck with your rig
 

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