DIY: Spark plug change

[gns100]

Hi all;

This is my first post. I read the original post to help me with my spark plug change at 90K. I modified the installation procedures as follows:

Pre-installation: check outside temp (30 degrees F) at 10am. Prep smoker, dry rub rib roast, place in smoker. Put turkey bones in pressure cooker with noodles, pressurize and cook 15 minutes, let naturally depressurize, put in vegetables, pressurize, turn off heat and let depressurize. Sample turkey noodle soup. Check outside temp (36F) at 12:30pm; decide to begin installation.

Installation: Remove Injen shorty intake, pop off throttle body and clean (it was pretty dirty). Take out spark plug #6. Notice gap appeared large. Go in the house and take out gap gauge and notice gap is 0.075 (all subsequent plugs were around this gap). Eat more turkey noodle soup. Install #6, and do #4 and #2. Reinstall all parts and nuts and bolts on driver side. Move onto passenger side and do all spark plugs on this side. One hint to get #5 coil out, put 10mm on extension and put on harness bolt and leverage wires out of the way. I was having some problems with #3 and #1 until I snapped off the plastic piece routing wires around these two plugs. Install plugs and reinstall all hoses, nuts and bolts. In between each plug I made sure to check rib roast, and at one point I placed remaining soup in the refrigerator. I also did not detach the wiring to the coil as there was enough play in the wiring.

Post-installation: Took car for test drive and appeared to run fine. Decided to floor it on a freeway on ramp , had to brake hard before I reached the freeway, because I was already up to 80mph. Get home and before shut down notice my car is now idling at about 825rpms. I guess I'll need to figure out how to bring that down to the 650+/- stock. Take rib roast out of smoker (140F) nice and rare. Let roast sit, and prep fixings. Eat a nice meal.



So anyway, has anyone else noticed that their old spark plugs have such a large gap? It seems as if the point burned down. I'm somewhat surprised the car was still running as well as it was (30 light-footed mpg).

[gns100]

OK, here's a followup to my post (#46). I took my car in to an installer for an exhaust and dyno tune with Osiris (as I don't want to hijack the thread, I'll talk about these on another thread). I showed him my spark plugs I just replaced and asked him why the gaps were so large. He immediately told me the electrode tips were melted away from excess heat due to an extremely lean condition, possibly because of the shorty intake (installed 30K ago) and/or manifold spacer (installed about 3K ago) that was added. He mentioned the performance and mileage gains I noticed were probably because of the lean condition, but said it was not a "safe" gain. I hope I was lucky and caught this before any real damage to my engine occurred.

Anyway, takeaways from the experience are: 1) it's probably a good idea to check your spark plugs (maybe just a couple) between the maintenance intervals, and 2) it may be money well spent to have your ECU mappings updated after changes that alter air flow which the air sensor misinterprets and leans out the mixture.

[scarface_613]

woohoo

[NismoG3505]

Very nice write up! i just did my plugs... took about 1:15. i got the NKG Laser platinum plugs ($22 each! ... but i feel worth it). Anyways, i have a tip for everyone that will help a lot ESPECIALLY on the passenger side... instead of removing the plugs from the coils BEFORE taking out the bold holding the coil... remove that bold first and the coil will be loose so you can manuever your hands and fingers much better to get the plugs off, this helps a TON on the passenger side... also re-attach the plugs to the coil BEFORE screwing the coil back down, unfortunately i didnt think of this simple method before doing the whole driver's side and half of the passenger side...but when i realized and did it this way it was a breeze... i actually got the passenger side all back together in about half the time as the driver's side
thanks again for the write up, i would have been lost w/o it!

[Infinite27]

I'll be doing my spark plug change sometime in the spring when it's nice and warm out.

Quick question.

Are spark plugs universal? which ones will fit my 04 g35x sedan?
Will the one mentioned in the 1st post : LFR5AIX-11 fit my G?
If i have a lot of options, which ones on the market are considered the best?

Thanks

[bythabay]

Originally Posted by Dan_K

What's the difference between LFR5AIX-11 and LFR6AIX-11?

It is stated in the owner's manual or service manual, but if I remember correctly, the 6a is one step cooler and is ok to use in any configuration.

[Dan_K]

Just replaced mine today. The come gapped at around .038". Nothing wrong with that, but I gapped mine a little wider at .044" since I'm NA.

[R1cky]

Originally Posted by bythabay

It is stated in the owner's manual or service manual, but if I remember correctly, the 6a is one step cooler and is ok to use in any configuration.

i got these from the dealer, is this the same as the oem???

[MetalCow]

I went to autozone and bought some of the replacement spark plugs. These were the oens recommended by their computer.

Bosch PLatinum +2

http://img145.imageshack.us/my.php?i...mg00011qd2.jpg

Will these do

[bythabay]

Originally Posted by MetalCow

I went to autozone and bought some of the replacement spark plugs. These were the oens recommended by their computer.

Bosch PLatinum +2

http://img145.imageshack.us/my.php?i...mg00011qd2.jpg

Will these do

IMO, I would stay away from those.

[bythabay]

Originally Posted by R1cky

i got these from the dealer, is this the same as the oem???

Those are indeed the oem plugs. The model # should match with the ones recommended in the manual.

[civic4982]

just printed this out and will do it in a couple days.

[MetalCow]

Originally Posted by bythabay

IMO, I would stay away from those.

Will do now the question is what to get, and does anyone need 6 boch +2 hahaha. i bought these about almost 6 months ago and have been in my trunk

[Extreme G]

Nice write up. thanks

[5150DS]

Man, what a pain in the butt the passenger's side is. I am pissed because I have 72k on my car and found oil on the #5 plug. Gonna try to get Infiniti to fix it.