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Spark Plug Change

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Today I did a spark plug change on my car at 16450 miles. I had to order the plugs (Motorcraft Iridium CFSY-12) at my dealer since I was the first mechanic to ask for them. All of the stock plugs read perfect with no signs of running lean or too rich. There is a slight oil film on the threads but electrodes and porcelin were light tan. Some pics of the removed plugs.
Sparkplugs002.jpg
Sparkplugs001.jpg

Easy job, Remove PCV hoses and coil covers, 8mm socket to remove coil hold down screw, 5/8" spark plug socket and 10" of extension. Unbolt coil, pull up a little release tab on harness and pull off wiring, remove coil and clean seals and blow out spark plug well. Remove plug (do with engine cool so you don't pull out aluminum threads) thread in new plug by hand until seated and torque 10 ft/lbs (124 in/lbs). Little dielectric grease in coil boot and push back into well, tighten coil hold down screw to 7 ft/lbs. Replace coil lead (make sure it clicks. Do 8 times and replace covers, and PCV hoses. Test drive and enjoy! Most of you won't be doing this for at least 40000 miles but I like to see what's going on with the engine.
Steve
 

TMSBOSS

Spending my pension on car parts and track fees.
7,530
5,247
Exp. Type
HPDE
Exp. Level
10-20 Years
Illinois
If possible, you may want to consider another dealership service department.

5 years 60,000 should cover the issues you have.

$400.00+ spark plug change OUCH.

Hope you have options.

Great to see a fellow Boss owner hooked you. Great guys....so I have heard!!
 
drano38 said:
Good news--a friend with a Boss 302 that rarely drives it (sad) let me take the part off his.
So I'm running again.
Picked up the spark plugs at Carquest, so after a Boss wash and engine cool down, I'll replace the plugs.
The dealer wanted to charge $346 for the o-ring TSB. I said that should be warranty, so they'll look into it more Monday. I'm still in the 5 year/60,000 miles, and since the o-ring is on the engine, I'd like to think that would be a power train item.
For the spark plug/misfire issue, the service ticket says he swapped #4 and #1 coils, and misfire stayed on #4. Hope is a plug issue and not a harness issue.

Part # BR3Z145268AA
They said it isn't on the '15 Mustang on their lot.

Here's a pic - It's the black plastic, with a 200 amp on left, 100 amp on right. Then 2 wires attach below that.
Thanks for everyone's help.
Glad you were able to get back up and running. I am lucky to have a couple good experienced dealer tech that works on my Mustangs. They were able to cure the misfires with new coils and the CPS issue with a new CPS. Hoping yours isn't a harness issue, but you should be throwing some codes if so. I wonder how many misfires there are on our engines that we don't "see" without the IDS tool. Hopefully your harness doesn't become a problem at your track event. They typically start intermittently and get progressively worse. Do you have a code reader you can use at the track to read and clear DTCs? If it does start and it's not too severe you might be able to just clear the codes between sessions and keep going.
 

TMSBOSS

Spending my pension on car parts and track fees.
7,530
5,247
Exp. Type
HPDE
Exp. Level
10-20 Years
Illinois
A code reader is a good idea even for those who are not tech savvy.

Two weeks ago at VIR I threw a 0315 code, went into limp mode and lit up the dash. Yea....fun.

The reader I use has software to diagnose the problem. Said I needed a relearn. I called the local Ford dealer and got the car in and out in 2 hours...include drive time. Since it was a three day event, this saved 10, 25 minute sessions for me.

Readers start under $100.00. Saved me from heading home early from a $600.00 event.
 

drano38

Wayne
1,130
318
I've got the Aeroforce gauge, so I can read and clear codes. I need to get into the habit of checking for codes after every track session, and weekly for daily driving.
Last fall at Hastings it threw codes more often than it had been, so that's why I had the o-ring TSB done this week. Should have done it last fall so they would have had 6 months to find a blown fuse. ::)

Gary, glad you've got some good techs. Maybe I need to make that 50 minute drive down I-29 for service.
 
drano38 said:
I've got the Aeroforce gauge, so I can read and clear codes. I need to get into the habit of checking for codes after every track session, and weekly for daily driving.
Last fall at Hastings it threw codes more often than it had been, so that's why I had the o-ring TSB done this week. Should have done it last fall so they would have had 6 months to find a blown fuse. ::)

Gary, glad you've got some good techs. Maybe I need to make that 50 minute drive down I-29 for service.
Might not be a bad idea if you keep having issues. They have two outstanding Master Mechanics and really understand the electronics side. I'm hoping the O-ring solves it, but you also may have a bad CPS like I had. Didn't seem to pull timing, just a confused sensor so it might be something you can live with at the track if it acts up, but will want to get it fixed when you get home.
 

drano38

Wayne
1,130
318
Spark plugs went in great--thanks to this thread. Just under 2 hours, but I took my time.
Let her idle for about 10 minutes, and all sounds good.
I did put a very small amount of anti-seize just above 1/2 way up the threads.
Here's a web site I found also that gives very detailed spark plug change directions and pics. But doesn't list the torque settings.
http://www.paulstravelpictures.com/Ford-F150-Coyote-V8-Engine-Spark-Plugs-Replacement-Guide/index.html
I converted the torque to inch/pounds, but that was at the top end of that wrench. It seemed pretty tight, so I backed off the setting just a bit, about 220 instead of 240 inch/pounds.
Going to a car show Sunday, so hope it gets me there and back. Then bed some new PFC 08 pads for next Friday.
Thanks again for all the help guys.
 
Just FYI, the online ford service manual calls for 124 lb-in for the spark plugs.

Glad everything's working out prior to your event. Also, aren't TSB's supposed to be free?!
 

drano38

Wayne
1,130
318
plugs 124 inch/pounds?
Steve's first post on this thread says 20 ft/pounds.
I can't open the service manuals on my mac--maybe I'm not smart enough.

So what's everyone using for plug torque? From this thread, Steve, Drew and Gary have changed them once or more.
 
I was checking the 2011 online service manual a couple of days ago and I made a note of the torque value, because I was going to need it in a couple of days.

Here's a screenshot of the manual
Sparkplug_zpslz54vmmm.png
 
drano38 said:
plugs 124 inch/pounds?
Steve's first post on this thread says 20 ft/pounds.
I can't open the service manuals on my mac--maybe I'm not smart enough.

So what's everyone using for plug torque? From this thread, Steve, Drew and Gary have changed them once or more.
I follow Steve's instructions to a T. 20 ft/lbs.
 

steveespo

Lord knows I'm a Voodoo Child
Moderator
4,008
1,924
Exp. Type
W2W Racing
Exp. Level
10-20 Years
Cookeville TN
I actually think they changed the torque spec from 240 in/lbs to 124. Sako is right, the current online manual is updated to 2013 and 14 for some sections. Your plugs are fine, just never remove or install when the engine is hot or dead cold, and I put a wipe of copper anti-seize on the threads which others say is a no-no.
Steve
 
steveespo said:
I actually think they changed the torque spec from 240 in/lbs to 124. Sako is right, the current online manual is updated to 2013 and 14 for some sections. Your plugs are fine, just never remove or install when the engine is hot or dead cold, and I put a wipe of copper anti-seize on the threads which others say is a no-no.
Steve
Good to know. You should probably update your first post to the new torque spec.
 
Brandon302 said:
What is the magic trick you guys are using the release the locking mechanism on the spark plug power connector?
I use a small flat screwdriver and slide it under the locking tab and lightly lift on it to release the connector while pulling it off.
 
cloud9 said:
I use a small flat screwdriver and slide it under the locking tab and lightly lift on it to release the connector while pulling it off.
Thanks, I had a hell of a time and didn't want to break the tabs.
 

ArizonaBOSS

Because racecar.
Moderator
8,730
2,734
Arizona, USA
Those tabs are pesky. I do the same as mentioned with a flat blade, but patience is required. They seal very well, so wiggle it a little bit while applying pressure and you will hear them break free. Don't get overzealous or it will get spendy quickly. I use the screwdriver between the harness and the COP but again, be very careful.
 

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