New spark plugs, but I think 100K is correct
11-22-2012, 05:02 PM
#1
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New spark plugs, but I think 100K is correct
So I installed new spark plugs this morning and I have to say for 91K miles, the plugs look great. I replaced the stock plugs with 1 step colder NGK LFR7AIX. While under the hood, I installed two in line catch cans and have a third on its way for the 3/4" vent.
Tools needed :
(1) T27 bit
(2) 17mm open end wrench or better yet spark plug wire puller
(3) small spark plug socket (I'll check the size)
(4) magnet pole in case you drop something
(5) socket wrench & torque wrench
Steps :
(1) Remove the air intakes
(2) Pop-up the air filter intake
(3) remove entire intake as one connected piece by prying the two black plastic clips on the throttle body
(4) open all the sparks plugs & check gap (0.031)
(5) spread a light coat of anti-seize on the spark plug threads
(6) Use the T27 bit to remove the bolt on each coil
(7) pull off the spark plug wires using the 17mm open wrench....do not pull on the wire
(8) then lay all four coil on top of the valve cover
(9) remove the old spark plug and install a new one and torque to 20 ft-lbs
(10) after all the plugs have been replaced, put the wires back on the spark plugs and use the open ended wrench to snap onto the plug (it is very tight)
(11) finish both side
(12) after both sides are done, reinstall intake
My recommendation for anyone wanting to replace the plugs :
(1) Remove the coils (makes accessing the plugs easier)
(2) Removing and installing the spark plug wires requires some serious force...more than I am accustomed to....I used an open 17mm wrench to pull off and pop on
(3) Buy all the supplies to replace the valve cover gaskets as you likely need to do them too
I'd budget 2 hours or more if you are super OCD....
Tools needed :
(1) T27 bit
(2) 17mm open end wrench or better yet spark plug wire puller
(3) small spark plug socket (I'll check the size)
(4) magnet pole in case you drop something
(5) socket wrench & torque wrench
Steps :
(1) Remove the air intakes
(2) Pop-up the air filter intake
(3) remove entire intake as one connected piece by prying the two black plastic clips on the throttle body
(4) open all the sparks plugs & check gap (0.031)
(5) spread a light coat of anti-seize on the spark plug threads
(6) Use the T27 bit to remove the bolt on each coil
(7) pull off the spark plug wires using the 17mm open wrench....do not pull on the wire
(8) then lay all four coil on top of the valve cover
(9) remove the old spark plug and install a new one and torque to 20 ft-lbs
(10) after all the plugs have been replaced, put the wires back on the spark plugs and use the open ended wrench to snap onto the plug (it is very tight)
(11) finish both side
(12) after both sides are done, reinstall intake
My recommendation for anyone wanting to replace the plugs :
(1) Remove the coils (makes accessing the plugs easier)
(2) Removing and installing the spark plug wires requires some serious force...more than I am accustomed to....I used an open 17mm wrench to pull off and pop on
(3) Buy all the supplies to replace the valve cover gaskets as you likely need to do them too
I'd budget 2 hours or more if you are super OCD....
Last edited by cij911; 11-23-2012 at 01:04 AM.
11-22-2012, 05:55 PM
#3
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I had my passenger side head gasket go which kinda started off my first build with ported heads. They are pretty easy to do to be honest. A lot easier than you would think and I had Blackbenzz there helping so it was a breeze.
11-22-2012, 06:06 PM
#4
MBWorld Fanatic!
Thread Starter
11-24-2012, 01:58 AM
#5
How exactly is the 17mm wrench used to take off and reinstall the wires? I plan to do the plugs next week and have the tools but could use a tip on the wrench use.
Used as a pry to get the wires loose? Then going back on is there a ridge on the wires or a fitting to wedge the wrench for leverage.
Used as a pry to get the wires loose? Then going back on is there a ridge on the wires or a fitting to wedge the wrench for leverage.
11-24-2012, 09:04 AM
#6
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Thread Starter
How exactly is the 17mm wrench used to take off and reinstall the wires? I plan to do the plugs next week and have the tools but could use a tip on the wrench use.
Used as a pry to get the wires loose? Then going back on is there a ridge on the wires or a fitting to wedge the wrench for leverage.
Used as a pry to get the wires loose? Then going back on is there a ridge on the wires or a fitting to wedge the wrench for leverage.
11-24-2012, 11:58 AM
#7
MBWorld Fanatic!
Yes exactly. IMHO a spark plug wire puller is even better, but the 17mm wrench works fine. The trick is making sure the connectors are fully seated on the re-install. Others have reported their wires were not tight, but mine were crazy tight and required a lot of force (more so than any other car I have ever worked on) to get the connector fully seated.
+ the fact that the plugs can have a tendency to rust and seize in place after a long period is why many suggest replacing them before 100k.
Glad you didn't have any issues there!
Thanks for the write up.
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11-24-2012, 12:16 PM
#8
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Thread Starter
Just to confirm, my spark plugs came out easily (no indication they were even close to seizing to the head), but I did use anti-seize grease on the new plugs to make sure they are easy to remove for the next person....What was crazy tight is putting the spark plug wires on the new NGK plugs. I believe the tip is slightly larger than the factory plug, thus making it quite snug...
