View Single Post
      11-10-2018, 12:42 PM   #148
RedCardinal
Private
United_States
31
Rep
69
Posts

Drives: 2013 M3 e93
Join Date: Oct 2012
Location: windy roads, hopefully

iTrader: (0)

After watching a few videos and reading some other posts, I did my first spark plug change on my e93 M3 a few days ago. I like OP's method of getting to the plugs over others, because this way there are the fewest things to take out or move.

TL:dr: Get the coil pulling tool. Absolutely use a universal joint with an extension and a swivel spark plug socket - and have several lengths of extensions. And finally, try a 6.5x150 flathead screwdriver and some penetrating oil if you over-tighten the spark plug and break off the threaded part.

I was initially against getting the coil pulling tool, preferring to jerry-rig a wire-hanger or use ethernet cable instead of spending money on it. However after reading other posts of people saying it sped the whole thing along, I decided that for me, speed was more important that doing it for free with existing things. Mostly because I was doing it in my apartment building's garage and I'm not supposed to be working on the car in there. So I wanted to get it done quickly.

I can say that it's great. I pulled out the easy-to-access coils in a second. Even the difficult ones took me a few minutes max to figure out (using a long screwdriver to lever out the tool was helpful).

For the actual spark plugs, I used a swivel spark plug socket - but also a universal joint, and few different length extensions. This was the only way for me to reach the difficult spark plugs and it was not difficult to do. Having the universal joint in particular was great.

My only surprise was when I was using the torque wrench on the 6th new plug when suddenly and for no reason, I over-tightened and broke the threaded part of the plug off, while it was threaded in the chamber. I didn't overtighten it past the click much, but much isn't required at that point before it breaks. I didn't realize something was really wrong until I tried to unscrew the spark plug and sparks came shooting out of the chamber. I pulled out the socket and saw the "naked" spark plug still in the spark plug socket but missing the silver threaded part, and said oh shit.

I opened the trunk and disconnected the negative battery terminal. This was particularly unfortunate for me because I am overdue (now) for emissions inspection and every time I disconnect the battery (I just replaced the EDC), I reset the computer.

Breaking it off also bummed me out for a few other reasons:
  • I had just done 6 other plugs and torqued them to one click so wtf was I thinking.
  • I was not supposed to be doing this in my apartment building's garage so I was trying to get it done quickly;
  • Because I wasn't supposed to be doing this there, I hid the car in a spot that was difficult to see, which was between a few tight support pillars;
  • If I couldn't get the threaded part out, the car would have to be towed from between these pillars, on the LL floor of an underground garage with tight maneuverability.




Anyway: I did the last sparkplug change and then started googling. One of the great things about the internet is, you're not the first to do that dumb-ass move. I was pleasantly surprised to find a whole bunch of hits right off. I read one account of someone using a flat-head screwdriver and some penetrating oil. Ok. So I get a few flatheads, and eyeballed their widths against an old plug: my goal was to find a screwdriver that was about the same width or a tiny bit wider.

I ended up using a 6.5x150 screwdriver (6.5mm tip, 150mm in length). I sprayed wd-40 on it (the penetrating oil I had around) and some in the chamber to try to coat the threads of the spark plug piece. I was not psyched to spray penetrating oil in the chamber, but I had read it was ok. Later when I warmed up the engine I saw some smoke and got a horrible smell, but I turned off the car and didnt see it again.

Although I suppose I should have waited longer for the penetrating oil to penetrate, I only waited maybe 5 minutes before inserting the screwdriver into the chamber. When I felt the screwdriver scraping against the threads, I gave it a few firm taps.Then I slowly turned it to the left, in the hopes that I was unscrewing the piece. It felt like I was - there was some firm resistance. I kept turning to the left and then the resistance disappeared! I was psyched. I pulled the screwdriver out and - no part. I stuck an extending magnetic tool down there and that grabbed it. I made sure that I had all the pieces by comparing it to a plug I had just removed. The little washer had also came out.

Then because I only had ordered 8 plugs, I didn't have another one to put in the car, until - duh - I realized I had 8 plugs I could use. So of course I put an old one back in until I could order up a new one.

As Sean Connery said about torque wrenches, "One click only, Vasili."

Last edited by RedCardinal; 11-10-2018 at 01:44 PM..
Appreciate 1
shimmy232330.00