The FSM (in that link I gave) shows the torque spec as 14 ft.lbs.

 

Ahh kk thanks! I'm still holding off on replacing them cause the 2 cylinders inside looks pretty hard to reach. When is it recommended to get them replaced distance wise?

 

I'm pretty sure it is something like 105K miles.

EDIT: Yep, there it is (on page MA-6) http://www.nicoclub.com/FSM/G35/Sedan/2008/MA.pdf

 

Did mine at 105K, they still worked but after replacements and many ECU resets I gained MPG.

 

So as long as seals aren't leaking it should be ok to wait til 105k? I did the l fab seals bout 2 or 3 years ago still solid.

 

I did my spark plugs around 70k and TBH, the ones that came out looked fine. Used, but in good condition.

I didn't have a spark plug socket, but did have a deep socket, so I took some electrical tape, did the double-stick method, and it allowed me to unscrew the plugs and gripped onto them to take them out/put them in without them falling out.

My car did feel better afterwards, but I also did:

Air intake track cleaning
TB cleaning
New air filters
New serpentine belt
MAF cleaning
Engine oil change
Transmission fluid change
Diff oil change
New brakes and rotors
New sport sway bars and bushings

So the car felt great, likely a cumulative affect of everything being done at once.

 

Does this method of changing spark plugs also apply to the 2006 Sedan models? I was thinking of doing mine and this thread has given me some encouragement....

 

I would imagine it is the same for the older G35. It's the same for any car, just different sizes I would imagine and what would be in the way to be removed first. I finally got my hands on some Bosch Iridium plugs planning to do mine this weekend.

 

Aww, man..wish you would have said something first. The Boschs are really nice at first, but they foul pretty quickly. The NGK Laser Platinums are a lot better. Those Boschs won't last more than 30k.

About the process tho, guys: its really much more simple than people make it seem. All you have to do loosen that big harness so its malleable and you can pull all the plugs fairly easily. Just be careful with the coil pack fastener bolt.

 

Cool, let me know how it goes... post a pic if you can.

 

Awww darn haha I didn't know that everyone I knew recommended Bosch or NGK, went with Bosch cause of the iridium. Oh well they were pretty cheap at NAPA only 6 bucks each at where I am. I'm 100% sure these are pre-gaped, but anyone know what the gaping should be? I just want to double check.

 

Personally, I'm not a fan of Bosch plugs. I'd much prefer either the stock Denso or NGK over them.

Plug gap spec is shown here: http://www.nicoclub.com/FSM/G35/Sedan/2008/MA.pdf (page MA-38)

A word of caution - DO NOT set the plug gap on an iridium plug like you would on an old lawnmower (i.e. by wedging and prying against the center electrode to widen the gap). If it needs to open, you must only grip and flex the outer ground electrode arm discretely using an appropriate gapping tool or some fine needle-nose pliers. http://densoiridium.com/installationguide.php

 

Anyone have the exact parts number for the NGK laser plugs? I ran into a little problem trying to put in my Bosch plugs, The bolt size of the plug that is in right now is 15mm and the socket fits perfectly, however the Bosch plugs they are 16mm, so idk if the guy sold me to wrong ones or what but I can't fit the socket in. Meaning I can only get the old plug out but not the new plug in... Also I don't even know why the plugs that are in there right now is 15mm, I thought OEM was 14mm? so idk if they were changed out already or something I'm so confused right now haha. So I'm going to return them and get the correct NGK if anyone has the parts number.

 

ngk (6240) plfr5a-11

 

Not to be a dick sofa but arent u a veteran ? The stuff Ur asking I'd expect a noob to be asking