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DIY: Spark Plug Change for FiST

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218
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Location
Norman, OK, USA
#1
It's around that time already! While Ford owner maintenance guide state that sparks should be changed at 100k miles and Mountune states 10k miles, it's really up to you when to change the sparks. Fortunately, sparks for the FiST is relatively cheap. I picked up my set for $6.99 a piece from O'Reilley Auto Parts and decided to change my sparks at 23k miles.

Here's a really simple DIY guide to change your spark plugs on the Fiesta.

Items you'll need:
- Set of SP-532 Sparks
- Anti-seize
- 5/8 Spark plug socket, 8mm socket, and socket wrench along with extenders



1. Start off by lifting up the engine cover. Work from one corner to another to make it easier.


2. Unplug the spark wires by pulling back the small white tab until you hear two clicks. Then, simply pull it out.


3. Unbolt 8mm bolts holding the coilpack. There are 2 per coilpack.


4. Remove the coilpack by pulling it up. Wiggle it side to side to make it easier.


5. Loosen the spark plug by using the spark plug socket. You can use 5/8 deep socket if you don't have one, but it's easier with the proper tool.


6. Remove the sparks and see its condition.


7. Put small amount of anti-seize on the thread of the spark plug. Only small amount is needed and try to put them around the middle of the threads.


8. Place them back in the and tighten to 14 ft/lb. DO NOT OVER TIGHTEN!


9. Re-install the coilpack and the engine cover and you are done!
 


Messages
320
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59
Location
Newark
#2
They should be iridium, so they will last a while even with boost, but 100k is excessive on this engine IMHO. I will probably do 60k stock, less with with tunes and track use.

Pretty standard 4 cylinder change. Nice writeup.
 


CanadianGuy

4000 Post Club
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Location
Southern Ontario
#3
[MENTION=731]chalituna[/MENTION] nicely done. One step I do before I start is either vacuum or use the compressor to blow any debris off the area. Just to be on the safe side. Could you update the original post with recommended gaping of the Spark plugs to have a "one post to rule them all"?
 


me32

1000 Post Club
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fairfield
#4
Thanks for the write up. Someone make this a sticky
 


Messages
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Location
Newark
#5
If they are iridium, they should never be gapped. I believe the gap is supposed to be <.032" and they come out of the box at .028" which is pretty typical for boosted engines I have worked on.
 


Messages
7
Likes
1
Location
Kalamazoo
#6
If they are iridium, they should never be gapped. I believe the gap is supposed to be <.032" and they come out of the box at .028" which is pretty typical for boosted engines I have worked on.
The only thing I have ever changed plugs on myself is my 91 K1500 pickup my lawn mower and my motorcycle. This is not at all like my old pickup. Pardon me for asking but once the coil pack is out the plug is just right below it? My car only has 4,000 miles on it so it will be a while before I change them.
 


codestp202

Active member
Messages
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Location
CA
#7
If they are iridium, they should never be gapped. I believe the gap is supposed to be <.032" and they come out of the box at .028" which is pretty typical for boosted engines I have worked on.
Some iridium need gapped. My denso's came .028, DHM asked me to gap them to .026.
 


neeqness

1000 Post Club
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LA
#9
What about the spark plug wires? Is anyone using any particular type/brand? I'm currently at +40k miles and considering replacing both wires and plugs.

Sent from my LG-H918 using Tapatalk
 


neeqness

1000 Post Club
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Location
LA
#14
Yup, unless neeqness meant replacing the coils themselves? [dunno]

(A total waste of coin, as long as they are all good and functional. ;) )
No, I just didn't know that it didn't have spark plug wires. First time changing spark plugs on this car (of which this is the first I've heard of not using wires) so I was just checking. Haven't looked at the manual yet for details on this maintenance.


Sent from my LG-H918 using Tapatalk
 


Last edited:
Messages
303
Likes
269
Location
Springfield
#16
I have just recently replaced my spark plugs, and I would like to add some thoughts to this topic.

I have a '17 FiST, and I'm just over a year into ownership with 15,000 miles on the odometer. Upon removing the coils, I'd noticed that the inside of the coil boots and the ceramic portion of the factory plugs had no application of dielectric grease. In addition, there was no anti-seize on the threaded portion of the plugs; I could immediately tell by all of the squeaking I'd heard while unscrewing the plugs.

I'm fully aware that most plugs these days have a special coating on the threads, but I had to use quite a bit of force while using a ratchet to unscrew them. I probably could have used a breaker bar to make life easier.

With this said, I am glad that I've decided to replace my plugs early. They're now sealed against electrical arcing, they'll be a lot easier to replace at 30,000 miles, and I know for sure that they are torqued perfectly to spec.
 


Messages
303
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269
Location
Springfield
#18
I am a proponent of skill and certainty; I do not depend on luck and chance.

Are you referring to the application of anti-seize? I noticed tiny metal flakes on at least one of the original spark plugs.

...or are you referring to the application of dielectric grease?
 


alexrex20

1000 Post Club
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Spring
#19
Both. I've been turning wrenches on all my cars for decades and have not once ever used dielectric grease or anti-seize on a spark plug. I don't even torque them and have never had an issue. But my arm is calibrated up to 200lb-ft +/-5. ;) lol
 


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