Spark Plug Replacement

[Ducati.Femme]

Hi All,

I've finally hit the mileage for spark plugs. And we all know that is the achilles heel to our horizontal 4's. Does anyone have a shop they would recommend to take my BRZ to for this? I'd prefer not to pay dealer prices, but I know that is an option.

TIA!

[bcj]

"They" recommend 60k miles for the plugs mostly to sell more hardware and service.
I put 90k on mine, but only changed them out because I needed a new throw-out bearing around then.

What is usually the weak link is the individual coils that bolt on top of the plugs.
Overheating at the track or idling in the pits is the most common coil killer.
It's not usually a problem driving around, even in the hills.
Those can be replaced fairly easily (sort of, depending on unbolting a few other things).

Changing out plugs can happen too. There's only four of them.
Unbolting a few other things, and a jack, or small hands in situ.

Generally any independent garage can handle it.
Subarus have been a commodity transaction for decades.
I don't have local Portland recs though.

[Aztec]

Originally Posted by bcj

"They" recommend 60k miles for the plugs mostly to sell more hardware and service.
I put 90k on mine, but only changed them out because I needed a new throw-out bearing around then.

What is usually the weak link is the individual coils that bolt on top of the plugs.
Overheating at the track or idling in the pits is the most common coil killer.
It's not usually a problem driving around, even in the hills.
Those can be replaced fairly easily (sort of, depending on unbolting a few other things).

Changing out plugs can happen too. There's only four of them.
Unbolting a few other things, and a jack, or small hands in situ.

Generally any independent garage can handle it.
Subarus have been a commodity transaction for decades.
I don't have local Portland recs though.

I'll piggyback on this post and add that I have never had issues with my plugs, but I've had to swap out the ignition coils for cylinder 1 & 3 more than once.

Specifically, this is a common problem when there is an aftermarket header that isn't wrapped and the repeated heat cycles in aggressive driving causes them to fail.
(I believe the latest revision of the BRZ coils have mostly mitigated this issue. Might be worth swapping them if you haven't done so before & do plugs and coils at the same time)
~

Originally Posted by Ducati.Femme

Hi All,

I've finally hit the mileage for spark plugs. And we all know that is the achilles heel to our horizontal 4's. Does anyone have a shop they would recommend to take my BRZ to for this? I'd prefer not to pay dealer prices, but I know that is an option.

TIA!

Back to your original question, I personally have a contact out in Forest Grove, OR that is very competent and inexpensive.
However, I don't think that is physically very close to you. He's my main mechanic for my Edelbrock SC BRZ
(He works on Ferrari & other highly modified cars all the time)

Let me know if you're interested
- Aztec

[Ducati.Femme]

Forest Grove isn't 'right down the street' but it's also not that far away. I was wondering if the 60k was realistic, since I'm guessing all the newer plugs that are used across industry wise are closer to 100k (generalization of course)

However, having a dad that beat "take care of maintainance items, for the longevity of your car" makes me always take heed of these 'milestones' within car care.

Good to know about the coil packs. I don't really track my car, so hopefully this won't be as much of a problem for me, but always good to learn about 'fail points' within our cars. *Thanks to others!

[RToyo86]

With a 17 BRZ you shouldn't have coil pack issues. They resolved that issue on the 13-14s by then.

Find a Subaru shop locally if they exist. The job really isn't that difficult, just tedious. Can be done a few different ways depending on how shop wants to approach things.
I did it in 3 hours, almost 2 was fiddling with one side, once I figured out tool combination, other side went quicker.


Any shop that quotes $500+ is doing off book time.

[Ultramaroon]

Iridium tipped electrodes go hand in hand with miniaturized coil packs in all modern IC engines. The little chips on the electrodes reduce the voltage required to form the spark by focusing the active area between the electrodes. In my experience, as long as the electrodes still have those chips, the plugs are good. Plugs with burned electrodes quickly take out their coil packs because the increased voltage required to form the spark is also felt at the coil as the magnetic field collapses. Basically, the coil pack fails because it is forced to work harder than it should.

I've pulled perfectly good plugs from 200 Kmi engines and have no plans to mess with mine unless something else goes wrong. Not saying they're bullet proof. Just sharing my experience.

[Tokay444]

It’s a 45 minute job. Just do it yourself.

[FR-S2GT86]

And for God's sake, stay away from aftermarket plugs and cheap "OEM" plugs from Amazon! There are too many counterfeit parts out there on the market. Buy them at the dealer only and you won't have any issues.

[Ducati.Femme]

I've seen those videos, and as much as I want to use the 'touch' method to hopefully guess if the tolerances are correct after first throwing a socket down a blind hole, then the extention, then attaching the ratchet.. and reversing that procedure, I'd prefer to have it done slightly faster and a bit more accuracy. Plus it feels like the 16+ model years have a slightly different layout with way less space to cram my hand down the side of the wheel well. *shrugs*

[Tokay444]

Tilt the engine like a non-moron.

[Teseo]

Kevin vo have nice tutorial. The combination of tools and the right procedure

[Dadhawk]

Originally Posted by Ultramaroon

I've pulled perfectly good plugs from 200 Kmi engines and have no plans to mess with mine unless something else goes wrong. Not saying they're bullet proof. Just sharing my experience.

Mine had 104,000 miles on the OG plugs. Had them replaced with the valve springs. Replacement set was still going strong 130000 miles later.

I don’t recommend that to anyone but I was never concerned about it. If I was tracking I suspect it would have been different of course,

[Ultramaroon]

Originally Posted by Dadhawk

If I was tracking I suspect it would have been different of course,

Not necessarily. I'd inspect and decide then. Likely just clean threads and reinstall. Think about your periodic aircraft engine inspection. Those plugs are expensive. Every decent A&P mech has a plug cleaning sandblaster. At least they did forty years ago.

[Dadhawk]

Originally Posted by Ultramaroon

Not necessarily. I'd inspect and decide then. Likely just clean threads and reinstall. Think about your periodic aircraft engine inspection. Those plugs are expensive. Every decent A&P mech has a plug cleaning sandblaster. At least they did forty years ago.

True. I saw the plugs that were removed when they did the valve spring replacement. After 100K miles, they still looked 85%. Since they basically replaced them for material costs though I had them go ahead and do them.