Spark Plug Install Instructions

Leeloo Dallas Multiquote for printing...

 

 

Thanks for all the tips everyone, I'll let you know how it goes.

 

I'm a little offended that none of my tips were included....

- ditto -

Well, damn, lol... I'm not reading through it again

 

*Okay, I re-read your posts whiners SBT - I did buy that doubled ended slim ratchet last night, and drewk2 - I'm going to try it without jacking the motor first.

Edited August 10, 2012 by Turkeylord

And the tip about making sure you reinstall your O2 Senor wire support bracket on the #4 coilpack screw. Easy to overlook .

 

Love that two-ended (1/4" and 3/8") thin ratchet. Use iit all the time and saves carrying two ratchets when this one will do for your car tool bag.

^ Yes, that too, thanks!

 

So, my findings...

 

-Flipping both rear coil packs made removal a snap.

-I only had to unplug the #4 coil pack.

-The Gearwrench socket/extension worked great. Magnet instead of rubber, and no risk of losing it in the hole due to the captive nature of the built in extension.

-I eventually wound up using a universal, then another 4" extension on that to the ratchet. Really put the ratchet out in clear space.

 

A buddy and I seafoamed the engine to clean the upper cylinders, pulled the old plugs, did a compression test, installed new plugs, and just about polished off a 12 pack in 2.5 hours.

 

In case you're wondering, 125, 120, 119, 121. Whew!

If you don't wear gloves while performing this procedure, DO NOT clean your hands with carb cleaner. IT BURNS! My hands look like I got in a fight with a herd of cats.

Did mine last night. It really wasn't as difficult as I was expecting it to be. This was my first time changing spark plugs in a car and I was taking my time, so it took me a little over 3 hours from getting all the tools out to starting the car to go for a test drive. It does seem to run a little smoother than it did before. I don't know how long the old plugs had been in there because I just bought my car and didn't get a very detailed service history, but they did look pretty bad so I'm glad I did it.

 

The only problem I ran into was that the clip on the wire harness for cylinder #3 coil pack snapped off when I pushed in on it to unplug it. I just put a zip-tie around it to hold it on and will check back in a couple of days to make sure the zip-tie is holding up to the heat.

 

I highly recommend lubricating the threads on the new plugs because it makes it much easier to thread them in by hand and it's easier to tell when the crush washer is seated against the cylinder head.

 

Thank you Boxer for writing the walkthrough and thank you to everyone else for all the tips!

What did you use to lubricate the plug threads?

I used motor oil

Anti-seize works well too.

My car has 69k miles. I am fairly positive that the plugs have never been changed. So if this is the first time, should there be anything else that I should change out along with the plugs? What type of plugs should I use for best performance?

Well, the 60k service includes:

 

Oil change

Rotate and balance tires

Transmission flush

Differential flush

Brake fluid flush

Coolant flush

Accessory belts

Spark plugs

 

If the rest of that hasn't been done yet it's a good idea. Also, if you're interested in cleaning the upper cylinders (Seafoam, etc), you'll want to do that on the old plugs.

 

As far as plugs go - OEM. I got mine here:

http://www.infamousperformance.net/servlet/the-659/Subaru-OEM-NGK-Iridium/Detail

Did the job this past saturday and it took 2 solid hours. The only hole that gave me issues was the DS rear, as the coil boot did not want to seat right. Took about 10 tries, but it finally went on right. Also, when I checked the new plugs all the gaps were too small. Had to open up all 4 to the .030 mark. Glad I checked this before putting them in. Thankfully the old plugs did not look too bad for being original with 67,000 miles. Car seems to pull a bit stronger with the new plugs. Very do-able job with the right tools. Best advice is to have several 10mm, 12mm and plug sockets available. By having shortys, deep socket, and standards of all (happened to have a shorter plug wrench that gave me a tad bit of extra clearance for the DS rear) three....your life will be a whole lot easier. Nice thing about this job is it also afforded me the opportunity to clean out the engine bay a bit. Shop vac was able to suck quite a bit of leaves and other crap out of there.

After sifting thru this thread, I'm liking the idea of jacking up the engine a bit more and more. Especially on my '08.

 

Anybody have any additional hazards I should be aware of when doing this ?

Just make sure you undo the dog-bone between the engine and the firewall. You can jack it easily without impingement issues. And put a piece of 2x6 or similar-sized wood between your jack and your oil pan - don't jack on the engine pulley.

 

And once you get your engine mount bolt clear, put the nut back on so it doesn't get a chance to bung-up the threads until you're ready to lower it.

[ame=http://www.amazon.com/NGK-Iridium-Spark-LFR7AIX-2309/dp/B003RYMPUY/ref=sr_1_2?ie=UTF8&qid=1348202211&sr=8-2&keywords=NGK+Iridium+IX+LFR7AIX]4 New NGK Iridium IX Spark Plug LFR7AIX # 2309 : Amazon.com : Automotive[/ame]

are these the correct plugs to buy? and i do not get the gaps thing what is that? i am new to this bought the car at 90k but i want to change the plugs cause im getting crap MPG and who knows if the last owner changed it...

4 New NGK Iridium IX Spark Plug LFR7AIX # 2309 : Amazon.com : Automotive

are these the correct plugs to buy? and i do not get the gaps thing what is that? i am new to this bought the car at 90k but i want to change the plugs cause im getting crap MPG and who knows if the last owner changed it...

From 1 page ago...

Most on here would recommend OEM spec plugs (NGK SILF6RA). They're a quality plug that's gapped correctly for our boosted engine and they'll last 60k+.

 

I got mine from Mike at Infamous.

http://www.infamousperformance.net/servlet/the-659/Subaru-NGK-Iridium-Spark/Detail

... i do not get the gaps thing what is that? i am new to this ...

I hate to sound condescending - because it pisses me off when people do this to me on other forums about other topics - but if you have no idea what the gaps thing is, perhaps you shouldn't be trying to do this work yourself. It's a little trickier to change plugs on Subies than on many cars, and if you get it wrong (cross threads, get crap inside the combustion chamber) it could be bad.

 

That being said, the gap is the spacing between the center electrode of the sparkplug and the thingy that is just above it. I find that on the plugs I get for my car, it is already preset to the correct gap. But I check it anyhow of course.

 

Good luck.

^ Yes. And if you do check the gaps (I did too) do it very carefully. The iridium electrode is fragile!

Changed out the plugs this morning. Didn't need to jack up the engine. Whole procedure went pretty well thanks to all the tips here. I really only had to take the 3 bolts out of the air pump so I could move it a little bit to take the plastic pipe off it.

Just rotated the pipe up and ziptied it out of the way. One tip I saw on another legacy gt forum was to use the handle from a floor jack between engine and frame rails to move the engine over a c.h.,. This saved alot of time getting ratchet on and off the extension on the passenger rear plug and to help get the socket and extension out of the driver rear. Seemed to be no danger of crossing threads. Plugs just slid in and started threading with no trouble using a little anti sieze. Was a different story on the '87 GL I had years ago. Mangled one of those plug holes !!

 

So glad this is done and that it went so well !! Big thanks to all who contributed to this walkthrough. I hope the timing belt change next year at 105k goes as well.

4 New NGK Iridium IX Spark Plug LFR7AIX # 2309 : Amazon.com : Automotive

are these the correct plugs to buy? i am new to this bought the car at 90k but i want to change the plugs cause im getting crap MPG and who knows if the last owner changed it...

These plugs are one step colder in rating than the OE plugs. Some people do use them. When I did mine a year ago I considered these but if you are stock and don't drive aggressively on a somewhat regular occasion you probably want the OE ones.

I havent read through this whole thread, but one tip that I found really useful was to use a length of hose on the spark plug to help thread it.

I just used some 1/4" fuel line.

That gives you and an extension on the plug, and also it wont get cross threaded as the hose will just slip if you dont have the plug threaded properly.

 

For my 98 Legacy GT, it made it easier to get to the deep spark plug hole.

I would like whoever designed these motors, to die a horrible death. I very nearly pulled an Elvis on my car last weekend.

Pulled an Elvis?

Pulled an Elvis?

 

Yah, he shot his Detomaso Pantera.