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2008 - DIY - N/A Spark Plug Replacement [Anal]!

('06-'08) 
176K views 236 replies 89 participants last post by  ottawa_boy 
#1 · (Edited)
N/A Spark Plug Replacement

Yes I am extremely anal when it comes to this stuff.

First Impressions:
1. First time is gonna' be long
2. Do the passenger side first bc after you remove the air filter housing..room is abundant. This will make it easier and make the driver side easier (for your first time).
3. Remove the air filter housing. Although I removed the Battery . it is NOT necessary
4. Changing plugs at 30K miles is nowhere necessary. But its good to do bc they will come out easier next time.
5. Have two 3" extensions ready on the driver side. You need to put the socket in in two steps (probably)
6. Do the job when the engine is cold.
7. Be prepared for a skinned knuckle or two
8. Its unlikely you will be able to use a torque wrench on the driver's side. Passenger's side probably you will be able to use one.

I have done several dozen plug changes in 45+ years and I would rate this as a '6' or '7' difficulty comparatively.

WRITEUP

Tools:

1. 5/8" Spark Plug Socket
2. two 3" extensions. (Driver side)
3. 8" to 10" extension (Passenger side).
4. Short handle ratchet (especially for driver's side)
5. 12 mm socket (Air Filter Housing hold-down bolts)
6. 8mm socket (Hose clamp -Air filter Duct to Housing)
7..Duct tape (Taping extensions/socket together)
8..Sharp Knife (Cutting away Duck Tape :) ) (or slashing your wrists-j/k)
9. Rubber Hose (Sucking/blowing debris out of spark plughole)
10. Anti-seize (Plug Thread * )
11. Dialectic Silicon Gel (Plug boots/Plug insulator)
11. Various Cleaning Supplies, flashlight, mirror, bandages, Whiskey, Beer, etc.
12. New Plugs
13. Ohm Resistance Meter (Optional)

Procedure:

* Gather up all tools ahead of time..make sure you are in the mood for this job.
* Do passenger side first.
* Insure car is cold.
* Remove air filter element
* Break connection where duct hose engages filter housing.
* Duct Tape upper filter housing toward the the fire Wall (so its out of way)
* Remove Lower bolts for lower filter housing (two- 12 mm). 10" extension is nice here.
* Housing may stick to lower mounting bolts-break free.
* Pull lower housing away from fender (air inlet) - remove from compartment.


* This is what you should be dealing with:



* Loosen guides for spark plug wires so you have flexibility in the wires.
* Grab the rubber handle on the boot and attempt to rotate the boot say 45 degrees in both directions.
* I'm not really sure rotating breaks it free at boot. Might be a waste of time.
* DO NOT PULL ON WIRE !
* Grab Boot at handle or anywhere except wire and Pull like hell..It may be ugly. :(
* Take piece of rubber hose, insert in hole and blow out debris.
* Tape 5/8" socket to 10 extension and put in hole and engage plug. (Insure you are engaged.



* Break Plug free and loosen very slowly. If it sticks go count clockwise and then counterclockwise in small increments
* Someone previously indicated spray brake cleaner for sticking plug (with extension spray tube).
* Remove plug, use hose to again blow out hole.
* Clean threads on old plug, lube with anti-seize* and run totally home using hand (no wrench)
* Lube new plug anti-seize* and use dialectic liberally on insulator.
* Run plug totally to seat using no wrench. Insure several times that it is seated.
* Torque to spec. (15.6 lbs) I used less ...(11 ft. lbs) With Anti Sieze
* The manual says to use 1/3 less torque when using anti-sieze. So that's about 11 ft. lbs
* The the correct torque will be 1/2 of a turn ( MAX) after "hand" contact
* Lube around housing and boot seal with dialectic.
* If you are going to check Resistance in Plug wires do it now
** Should be 9 to 16 Ohms. Use dialectic when reinstalling boots on supply end of wire.
* Push boot on plugs and 'feel' engagement.
* Repeat with other Plug.
* Reinstall Air filter Housing and filter.

*** Driver's side: (Battery removal not necessary)



* Utilize 3" extensions..tape one extension to socket.
* For removal, if extensions come apart its not a big problem you can push them together even if in hole.
* For installation, it the socket sticks to plug and the extensions come apart. You may need to:
*** Remove plug or
***Put a hook on a piece of wire and hook the pieces out (I needed to do this)
* Its unlikely that you will be able to use a torque wrench. Develop feel on Passenger Side ones. ( approx just about 3/4 turn after hand seating)

Other suggestions/Problems:

* Do two plugs and test drive, After cooling, do the other two,
* I didn't intend to do the job but after I pulled 2 plugs I went and bought Autolites bc NGK not available. Second time used NGK
* There is controversy about using anti-seize. I used it this time. I used 11 ft lbs with a small bit of anti-seize but later found: (from Subaru) Use 1/3 less torque with thread lubricant..11 ft lbs
* If you disconnect the battery, vehicle will not start on first try. Should start on second try.


If anyone thinks of other things, I'll add them

Oh..here's how the plugs looked after 31K miles

 
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5
#3 ·
I took the windshield washer reservoir and pump out to make the driver's side much easier (still not easy though). Took me one hour first time.

Would you recommend getting your oil tested every time yo do your plugs by blackstone? haha...
 
#6 ·
The battery can stay in but the windshield washer reservoir must come out. It helps if the thing isn't full to the top too.

A mechanics stick magnet works great if your spark plug socket doesn't hold the plug tightly and the plugs want to slip out. Just unthread the plug all the way, remove the socket and fish the plug out with the magnet.
 
#136 ·
The battery can stay in but the windshield washer reservoir must come out. It helps if the thing isn't full to the top too.
You don't really need to take it out. Try this instead.

First, unplug the electrical connection. Then, simply take out the two bolts which secure it to the vehicle. Lift the reservoir up and unclip the small hose from the side loom clip. At this point, you should able to rotate the reservoir and rest it on its side, on top of the battery. Mine was 2/3 full and nothing leaked out, but it wouldn't hurt to drain/siphon out the fluid.
 
#19 · (Edited)
ADC, Nice writeup.
The only thing that gave me a problem in the past is too much dielectric grease on the boot(s). I've backed off to the point that I just skim the inside if the boot with my pinky finger. The Tip Connector doesnt like the grease - though in theory it shouldnt be a problem. I clean the boots inside and out using ethanol mixed with a tiny bit of distilled H2O. Plug boots dont like salt from the road OR from your sweaty palms; it only takes a little to migrate and cause a high misfire count in humid weather. Same goes for the plug socket insulator. It shouldnt transfer dirty grease onto the plug insulator. I usually weAr clean latex gloves to handle the new plugs, then thread the plugs in with a piece of fuel hose then tighten without the plug socket rubber insert. Another biggie - normal folks dont understand high-tension wires and what they like and dont like; but they surely DONT like to be under strain or torsion; so let them droop naturally the way they want to hang and try to keep that orientation when you re-insert the boot. Add these hints to your tune up list and you should have a car that runs BETTER after a tuneup other than worse. BTW, these are some of my SCCA racing secrets for extra HP, so dont tell anybody;)
 
#21 ·
Couple questions:
1) What was Year and Model, Engine of car serviced
2) What plugs came out ( Make and part#)
3) What plugs went back in
4) Did it run any different afterwards with the Autolites, and how close was the autolite insulator length to the NGK/ND - critical for a pent roof 'hemi' head.

thanks Al.
 
#23 ·
Couple questions:
1) What was Year and Model, Engine of car serviced 2008 N/A
2) What plugs came out ( Make and part#) NGK FR5AP 11
3) What plugs went back in Autolite AP3924
4) Did it run any different afterwards with the Autolites, and how close was the autolite insulator length to the NGK/ND - critical for a pent roof 'hemi' head. Seems to run just the same. The length of the insulator/ground prong appeared the same but I didn't measure them

thanks Al.
Good Questions. You are welcome
 
#22 ·
My parent's old oldsmobile V6 was also a pain to change plugs on.. the front facing 3 were easy, the rear were right up against the firewall. You had to disconnect an engine mount and lean the engine towards to front to give yourself SOME room.. but still not enough to need new knuckles. :p
 
#24 · (Edited)
The spark plug tightening torque for my '03 X is 15.2 ft-lb. The instructions say this is for a new, dry (no lubrication) spark plug. If lubricated, the torque is to be reduced by 1/3, which makes the torque 10.2 ft-lbs.

Bobby...

['07 FSXT MODding Journal] ['03 X MODding Journal]
 
#26 · (Edited)
BTW, what's wrong with anti-seize???:confused:
There is just controversy as to using it or not.. As pointed out above you need to reduce the torque. I have seen info that some plug manufactures don't want lube on threads.

The spark plug tightening torque for my '03 is 15.2 ft-lb. The instructions say this is for a new, dry (no lubrication) spark plug. If lubricated, the torque is to be reduced by 1/3, which makes the torque 10.2 ft-lbs.
]What instructions are these[source]?..I'm not doubting you[/B]

Is using anti-seizing compound considered lubricating the threads? :confused:
I would say 'yes'

Bobby...
 
#30 ·
Just to report back. The Autolite Plats ($1.99) gave me the best mileage I have had thus far on the car. (32.4 mpg) now that was over only 250 miles but the other part of the trip included 40 miles of driving inside the Pittsburgh area and my overall trip mileage (474 miles) averaged 31.2 mpg). I intend to pull the plugs at 20K miles just to examine them. But this is the 4th vehicle I have had them in.

Changing them the second time will be a piece of cake...1.5 hours.

Autolite#..AP3924
 
#32 ·
hey now, youcan get some good dealership techs............i my mind what it comes down to is flat rate. when you pay a person for 1 hr, but you can do that job in .5 hrs, then you can make twice as much in an hr, but at the same time just because you an do it in a .5 hr doesnt mean its done the right way sadly, this coming from some who is going to school to became a tech and sadly i had to sit through 3 weeks of all that stuff, which is why i love diesel!!!!! hourly baby!!!!
 
#36 · (Edited)
I really was not aware of that. Not doubting you on this but where is that information?
If this is true, I'll have to pull them.

Additional Information: I called up Autolite Technical Service. They indicated that the NGK-FR-5AP-11 is a Heat Range "5". The Autolite AP-3924 is a Heat Range "4". The Last # is the Heat range. The next plug that Autolite makes is a AP 3926 which is a "6" heat range.

So based on that I will keep them in 10K and check them then.
 
#40 ·
Bosch plugs

I went to my local O'reilly Auto Parts store and asked for an equivalent plug to the OE. They sold me Bosh FR8DPX, which I think to be a hotter plug then recomended. At first it seemed that my car was gasping for air when I accelerated (which is weird because I am also running a K&N air filter and try to use 89 octane gas). Recently, to compensate, I ended up taking off the very first section of the "breather box"(?) (The front half of the air intake part that is removed to access the the passenger side pulgs.) It runs smooth now except for initial take off (from park) seems to be a big lag with a delayed "jump start" from setting still to moving. How does anyone feel about the effects of running hotter plugs in an 03 fx or any Foz for that matter? Note: Milage has always been with-in EPA estamated milage.
 
#41 ·
Dubaya, keep in mind many ppl at parts stores don't know this but...when it comes up in the computer as saying it "fits", this purely means it will fit but not necessarily be the right heat range. I was looking through the plugs recommended for my foz autozone, the NGK coopers were the only correct heat range out a list of maybe 15 plugs it says will fit.
 
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