Has anyone changed their spark plugs by themselves? Is there any special tool that we need to get just for the Gs? I am pretty hesitant to do it myself, I have done a lot of maintenance on my car (fluid changes, TB etc) however I heard some horror stories about spark plug changes, should I just leave it to professionals?

 

Hell yeah, man, do it.

It's super simple. All you need is a 10mm socket (to remove the 8-10 bolts that hold down the wiring harness around the plenum, as well as unfastening the coil packs), spark plug socket, a ratchet, a decent size extension (8" or so), and some anti sieze.

No prob.

There's a video on YouTube that shows you all the bolts to take off when loosening the harness.

 

Yeah do it yourself to save money.

 

It is an odd size spark plug (14mm), so often people just end up using a regular deep-well socket instead if a proper spark plug socket. It is not a problem if you have some means of reaching down into the tube to retrieve and reinsert the spark plugs after loosening/tightening. Many methods will work for that. Some use a length of vacuum hose slipped snugly over over the plug tip, but I found a simple pair of extra long reach needle nose pliers worked just fine for me. Basically, you just don't want to drop the plug down into the whole and have it close the plug gap on you.

ONE WORD OF CAUTION: DO NOT UNPLUG YOUR THROTTLE BODIES!!

It is an added hassle, but with a little effort, you can work around the TB's while they're still plugged in. Theoretically, you should be able to unplug them and then do the whole TPS/idle relearn procedures, but inexplicably, there are instances where, on certain cars, it just will not take and you can be forced to go to a dealer and pay for their Consult III system. Further, there are cases where even the dealer can't get it to take with the Consult and will start telling that you need to swap out the TB's or even the ECU ! And this is on cars which were previously running perfectly well, except that the damn plug was disconnected and then they can't get a relearn to take.

I'm not trying to frighten you away from the job, just offering a simple heads up to avoid any potential problems in the first place.

I recommend you use the specified Denso plugs, and you DO NOT need anti-seize on a new Denso or NGK plug, as they are already treated. If you do use it, your torque specs will be off.

 

i unplug my tb all the time. jus disconnect the batt before hand and u wont have issues

 

You can't really say that. You know what has worked for YOUR car, not what has happened with other cars. If they all behaved the same way, there would be no issue here. Unfortunately, they do not, and as such the absolute safest solution (and hence, recommendation) is to just not disconnect it.

.02

 

Who would and WHY would anyone unplug the TB to change the spark plugs?

 

Uhm, maybe cuz that's precisely what is says to do in the FSM** !!


Seriously, it does, and to be honest, it seems like a no-brainer that you should because you gain a whole lot more free access to the COPs and the plugs with them moved further out of the way. And if the stupid relearn worked in all cases as it should, there'd be do issues.

** ref: page EM-16 http://www.nicoclub.com/FSM/G35/Sedan/2008/EM.pdf

 

That's really weird. I never have. I just take off the bolts necessary to loosen the wire loom adequately. I may have the simplest way of changing the plugs. Maybe I should make a DIY video. I swear, I can do it in less than an hour and all I do is take off 8 or 10 bolts to loosen the wire loom.

 

^^ Hey, I'm not arguing with the "don't need to unplug" method at all, like I said that in my first post, it definitely can and should be done. Without a heads up though, it's not hard to see how someone COULD easily unplug them for more access room is all.

 

No, I know. I'm not saying it doesn't say it in the FSM, but I have definitely done it without it that's all.

 

I unplugged mine and I had no issues. Unhook the negative battery cable, follow the FSM, and everything should be fine. Pretty easy process, but it did take longer than I expected.
I didn't do any kind of "relearning" procedure on my '07. As for getting the plugs out with a 14mm, I stuck a piece of electrical tape on just one of walls of the inside of the socket. Wrap it around the lip of the socket a little so it'll stay in place. That provided just enough resistance to hold the plug.

I'm sure it can be done with all of that stuff in place, but since it adds about 30 seconds to the process to get it all out of the way, why not? That said, if there's an easy way to do it without removing all of that crap, I'm all ears.

 

my socket is special it holds the plug in place. for reals tho i thought all spark plugs sockets hold the plug in place so it wont fall out.

 

They do, it's just that 14mm is a (relatively) rare plug size, so the vast majority of people don't have a 14mm spark plug socket; instead they just use a regular deep well socket.

 

Oh kk cool thanks for the inputs guys! And do you guys torque the spark plug back on? what is the torque spec on our plugs? I think most of the videos I seen they didn't torque it and just did it by hand.