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Discussion Starter · #1 · (Edited)
I changed my spark plugs last weekend and I thought I would document it for the benefit of other less mechanically experienced board members like myself but who know just the basics.

My car is an E46 2001 325i. Spark plugs used : BMW OEM (NGK BKR6EQUP).
Tools needed: T30 Torx bit screwdriver, flat head screwdriver, ratchet, 10mm socket, 6" extension bar, 5/8" spark plug socket.

Step 1
Open the cabin microfilter cover and remove the microfilter. Unscrew the 4 Torx screws (T30) highlighted, in the microfilter housing. Carefully snap off the 4 clips holding the 2 cables in the front of the housing. Ease out the 2 cables from the clips. Lift off the microfilter housing.
 

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Discussion Starter · #3 · (Edited)
Step 3
Remove the 2 10mm nuts at the top left and bottom right of the coil. Plugs 1 & 6 have earthing straps.

Pull up the silver clip at the bottom of the coil with your fingers and gently ease out the connector. Now the coil can be lifted out.
 

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Discussion Starter · #4 · (Edited)
Step 4
Now using your spark plug socket with at least a 6" extension bar, you can remove the plugs and replace the new ones.

I used a high temp spark plug lubricant/ anti-seize compund so I tightened the plugs until just firmly tight. The spark plug torque is 30Nm otherwise.

Repeat the procedure for all 6 plugs and follow the reverse procedure to replace the microfilter housing.
 

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Stick Drive
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WAM said:
Step 4
Now using your spark plug socket with at least a 6" extension bar, you can remove the plugs and replace the new ones.

I used a high temp spark plug lubricant/ anti-seize compund so I tightened the plugs until just firmly tight. The spark plug torque is 30Nm otherwise.

Repeat the procedure for all 6 plugs and follow the reverse procedure to replace the microfilter housing.
Interesting, they are four pronged....
 

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I love my beautiful wife.
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Just used this DIY...excellent job.

Let me just add that after 53,xxx miles, my plugs had virtually no wear. I still replaced them with the OEM NGK's, however now I know I won't ever need to replace them again.

I believe they are truly 100,000 mile plugs.
 

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my 1st bmw
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Great write up i did this yesterday using this thread...i was affraid of breaking them when pulling the connector out but with a little force it came out no harm done...THANKS!!
 

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I noticed that too. I assume it allows for a bigger spark which give a more complete combustion of the fuel mixture.
There is no bigger/better spark or more complete combustion, if there was the MFG would be all over it since more complete combustion would gain lower emissions, more HP and huge tax advantages for pennies per car, it either sparks or it doesn't, no science or data at all to support that 4 prongs are better than 1,2, or 3.

Not to thread crap but its just bad info that gets past around a lot. Kind of like vented/slotted rotors ( with less braking area thus less friction material and correspondingly less braking efficiency) will somehow give better performance. They dont, never have, never will. Its a simple equation, how much surface area do the pads have to contact, take any away and the performance goes down.

One of the biggest waste of your DIY dollars and potentially the easiest to cause significant engine damage is using a plug other than that of the MFG's specs. The best part is the NGK OEM's are a few bucks each. People spend the price of a set of 6 OEM plugs for ONE Iridium or 4 prong or the latest rage plug, ask a mechanic, one you trust, dont take my word for it, he will tell you its snake oil.

Please dont think I'm calling anyone a liar or dumb, there is a lot of misinformation out there and this is something I know quite a bit about. Changing your plugs at 50K BTU is overkill, wasted money, if you can live with that then go ahead., but dont expect any tangible benefit, because you will not get any. You will one day, when the car wont start and after changing the failed plug /plugs then you will see the benefit, no sooner.

Its like a light bulb, it works or it doesn't, there is no in between:eeps:
 

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so are you saying you only replace your spark plugs when your engine won't start?

On Pelican's DIY page they say to replace every 10k which I think is excessive, but you're on the other end of the spectrum. I generally trust Pelican, though.
 

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so are you saying you only replace your spark plugs when your engine won't start?

On Pelican's DIY page they say to replace every 10k which I think is excessive, but you're on the other end of the spectrum. I generally trust Pelican, though.
Ideally prior to that. I would think any competent technician or DIY'r would see the lunacy of changing plugs at 10K intervals. Unless you had serious engine work, track the car, a lot...., or in the case of Pelican, sell plugs.

Take it for what its worth, its a cheap part of any maintenance regime, but it does come with a cost, a risk whatever you call it. If you have never installed a Helicoil insert into threaded head, I would use the money elsewhere.

That's just me, I have been wrong before, ask my ex....
 

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I recently changed my spark plug and it's totally different from yours. Mine has a flip switch that removes the connector from the socket. Then I just wiggle/twist the coil out of the socket. There is no nuts or anything to remove. I had all 6 of my coils change under recall though.
 

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Worst plugs ever....I had them in my 85 b/c they were listed as "OEM approved replacements" in the AutoZone computer....after about 10k miles I thought my fuel pump was dying. Swapped out to OE (which on mine is single prong platinum, not 4-prong) and it runs great.

Buddy of mine put those Bosch +4 Platinums in his Mustang and had the same problem, and I know a couple guys that have tried them in Jeeps with no success! I'd steer clear :)
 

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Upon a diagnostic check, #2 plug was found to miss. The dealer wanted $440 to replace 6 spark plugs. :yikes: I was able to politely say no thank you without a snear. Thanks for the detailed write up. It will definitely come in handy when I decide to replace them.
 

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*Åþråh Cådåþråh*
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Upon a diagnostic check, #2 plug was found to miss. The dealer wanted $440 to replace 6 spark plugs. :yikes: I was able to politely say no thank you without a snear. Thanks for the detailed write up. It will definitely come in handy when I decide to replace them.
Damn STEALERSHIP!!!!!!!!!!!!!!
 
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