Sweet. I plan to do this soon so I appreciate the guide. TY, sir!
DIY: 3rd Gen Spark Plug Replacment
6
Good morning everyone. Haven't seen one of these around here yet, and there aren't too many of us at the point where we need to do this, so here's a quick reference guide.
This is for replacing a 2014, 2015, 2016 or 2017 Mazda6 Skyactive 2.5L Spark Plugs.
The total process only takes 10 - 20 minutes depending on if you like to do all 4 plugs at once, or 1 at a time; I prefer the latter.
Things You'll Need:
Spark Plug Gap per the Manual:
Spark plug gap [PE01-18-110, PE02-18-110]
Standard: 0.75—1.10 mm {0.030—0.043 in}
New spark plug (reference): 0.75—0.85 mm {0.030—0.033 in}
Spark plug gap [PE5R-18-110, PE5S-18-110]
Standard: 1.05—1.40 mm {0.0414—0.0551 in}
New spark plug (reference): 1.05—1.15 mm {0.0414—0.0452 in}
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1. Open your hood (duh) and remove the engine cover by pulling up on it until the rubber plugs pop out.
2. Locate the 4 ignition coils and their individual 8mm nuts (Seen Below):
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3. Unplug the wire connector from the coil(s) that you plan to work with. Simply press the plastic center piece down and pull the plug out.
4. Unbolt the 8mm nut from the coil.
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5. Pull the coil straight up and out. Should come out without much force at all. (Sorry, no photo for this one).
6. You should now be able to see the plug waaaaayyy down. Time to get it out with the 14mm deep socket.
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7. This is where a magnetic wrench or spark plug socket REALLY come in handy. It's hard to tell, but I counted at least 15 full rotations for the plug before it could be pulled out.
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8. Compared to the new one it's not looking too bad for 83k miles!
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9. If you want to use anti-seize on the new plugs, that's never a bad idea. Just be ABSOLUTELY sure to get none on or anywhere near the plug tip. I like to leave about a quarter to half an inch of bare metal near the tip of the plug so there's no chance of any getting near it.
10. Install everything in reverse order and you're good to go!
This is for replacing a 2014, 2015, 2016 or 2017 Mazda6 Skyactive 2.5L Spark Plugs.
The total process only takes 10 - 20 minutes depending on if you like to do all 4 plugs at once, or 1 at a time; I prefer the latter.
Things You'll Need:
- Replacement Spark Plugs - I recommend stay away from cheap Denso from Amazon.
- Part Numbers:
- Boche: 9621
- Denso: 4711
- NGK: 94124
- 14mm Deep Socket (ideally, one with a magnet for removing plugs - seen in photo).
- 8mm Socket or Wrench, but socket works better.
- Socket Extension, yes even if you have the plug removal tool.
- Anti-seize (not necessary, but recommended).
Spark Plug Gap per the Manual:
Spark plug gap [PE01-18-110, PE02-18-110]
Standard: 0.75—1.10 mm {0.030—0.043 in}
New spark plug (reference): 0.75—0.85 mm {0.030—0.033 in}
Spark plug gap [PE5R-18-110, PE5S-18-110]
Standard: 1.05—1.40 mm {0.0414—0.0551 in}
New spark plug (reference): 1.05—1.15 mm {0.0414—0.0452 in}
1. Open your hood (duh) and remove the engine cover by pulling up on it until the rubber plugs pop out.
2. Locate the 4 ignition coils and their individual 8mm nuts (Seen Below):
3. Unplug the wire connector from the coil(s) that you plan to work with. Simply press the plastic center piece down and pull the plug out.
4. Unbolt the 8mm nut from the coil.
5. Pull the coil straight up and out. Should come out without much force at all. (Sorry, no photo for this one).
6. You should now be able to see the plug waaaaayyy down. Time to get it out with the 14mm deep socket.
7. This is where a magnetic wrench or spark plug socket REALLY come in handy. It's hard to tell, but I counted at least 15 full rotations for the plug before it could be pulled out.
8. Compared to the new one it's not looking too bad for 83k miles!
9. If you want to use anti-seize on the new plugs, that's never a bad idea. Just be ABSOLUTELY sure to get none on or anywhere near the plug tip. I like to leave about a quarter to half an inch of bare metal near the tip of the plug so there's no chance of any getting near it.
10. Install everything in reverse order and you're good to go!
1 - 20 of 47 Posts
I swapped over to the Bosch ones I listed in the OP about 15k miles ago and not looking back. Idle at times is a tiny bit rough, but I vaguely remember the OEM ones were the same. Low/Mid torque is back to normal and the smile has returned when getting on highways with my little 4-banger.
Again, totally agree with the observations on this board. I swapped the Denso's out for the Bosch Iridium and am glad I did. The low and mid-range torque has recovered and this thing is running pretty smooth for me now. I was able to get the Bosch plugs at Advance Auto for $19.70 total including tax so I'm pretty happy. I might look at OEM the next time around, but for $20 I'm satisfied with how the car runs.I swapped over to the Bosch ones I listed in the OP about 15k miles ago and not looking back. Idle at times is a tiny bit rough, but I vaguely remember the OEM ones were the same. Low/Mid torque is back to normal and the smile has returned when getting on highways with my little 4-banger.
On a related note, if somebody needs a 400-mile old set of Denso 4711 plugs cheap, I'm your man!
Part numbers are on the original post of the thread
Boche: 9621
Denso: 4711
NGK: 94124
1 - 20 of 47 Posts
