So I just had my plugs replaced by the dealer at 38,000 miles (thank goodness I bought that extended maintenance plan I went in for an oil change and they said the computer was recommending it. All lot of eye brow raising went around.

I didn't really have any symptoms other than a short bout of the countryman stumble that went away after I diluted out that tank of gas. And everything seemed fine other than the dealer telling me I needed plugs. I had to get gas in the middle of nowhere nevada and even though it was chevron, they were out of everything but premium, so I'm guessing even the premium was from the bottom of the tank.

I wish now that I had asked them to show me the plugs. I have been reading about hot vs. cold plugs and symptoms of lean/rich/carbon foul/water foul/ etc.

I have a JB+. I drive my car hard. Right before the stumble and the plug replacement I drove through death valley in the 101 heat followed by several hundred miles of two lane highway with lots of 100mph+ redline passing. Soooo much fun. The pull in fourth gear is

Anyway now I am curious about the plugs (wish I had seen them) and if we have cold or hot in this engine. So what kind of plugs should I have? Does lean = need hotter plugs?

I have the plugs here:

Cooper S, SX, JCW 12122293697
BERU 12ZR6-SPP2 -1

http://www.ecstuning.com/Search/SiteSearch/12122293697KT/





Cooper ( NON S ) BERU 12ZR6SP02 12122158165


http://www.ecstuning.com/Search/SiteSearch/12122158165/






From that you can see : i did not see much info on the beru page.

http://beru.federalmogul.com/e-catal...reference/Z332

So those are the stock plugs? but it's hard to get much info on them from the beru website? is that what I'm seeing?

Interesting, I wonder if anyone else out there has tried different plugs?

Thanks!

Yea, not much info , even from Beru. Those are the plugs.

http://www.burgertuning.com/mini_coo...t_adapter.html

Burger has the socket and plugs at a great price.

I wonder if the JB+ tune has anything to do with the plugs needing replacement so soon.

I know all the JCW engines for Gen 2 get the plugs changes at 30,000 miles. Cooper S and Cooper ~60k. Some cars with a AM Tune treat like a JCW engine for plugs is what I have heard in the past.

I retract the comment on Burger for the plugs. They are out of stock with no ETA. The socket is still good but don't order from their own site, instead order it from Amazon and save $2 shipping. I don't know why but Burger wouldn't offer the cheaper shipping that they offer if you buy from Burger but on the Amazon portal.

I found that NGK has discontinued the 5992 plug and replaced it with 5843. I found the current cheapest price and bought 4 of these on eBay today for $11.14 each. This plug is the new one for N14/N18 JCW from NGK.

http://www.ebay.com/itm/NGK-5843-Double-Platinum-Plug-/360803052865?hash=item540189ad41&vxp=mtr

Former JB+ owner here: Definitely get better plugs if you're using it. I noticed the difference right away. I got the ones from Burger Tuning mentioned above, which I believe are the stock JCW plugs. Easy swap, noticeable increase in response.

Getting plugs replaced around 40k sounds about right too FWIW.

Yeah, I think will switch them out soon. Do better plugs foul less? Or is that just part of the territory with mods?

I messed up and read the ngk discontinued chart and website incorrectly.

NGK 5843 is the old part # for non-S models

NGK 5992 is the old part # for S models

NGK ILZKBR7B8DG (95770) is the new part # for S models

NGK NGK PLZKBR7B8DG (90223) is the new part # for non-S models

So which ones are the JCW plugs from NGK?

NGK ILZKBR7B8DG (95770) is the new part #

" NGK ILZKBR7B8DG (95770) is the new part # for S models " where did you find this info for the N18 , I see it for the N14 engines ? NGK site goes to up to N14 only ? And most cross ref show the N14 also ?

Do you have a link ?

I found it on the NGK Canada site I think.

Yea, US site does not show that nor does any of my distributors for NGK, so hopefully its the same heat temp and thread depth.

Burger tuning confirmed the part for S models as the upgrade and standard for JCW.

Also found this link from NGK

https://www.ngk.com/learning-center/article/458/discontinued-ngk-spark-plugs

I bought the 5843 and returned for refund. I just received the 95770 and will be installing these either this weekend or next in preparation for MOTD.

So what does it cost to get the plugs replaced? I have 52,000 miles currently, so I am probably due.

Whats the recommendation...probably something more difficult to do? Mini Dealer? Independent Service Shop?

I would just do it yourself. It is very easy to do if you have a torque wrench with an extension. It takes less than 10 minutes.

This helps too: http://www.burgertuning.com/mini_coo...t_adapter.html

Pop the plastic engine cover off, pull on the four ignition coils get them off (twisting a little helped), then you'll see the tops of the spark plugs. Uninstall the old ones, drop in the new, tighten them up, reinstall the coils and fire it up to test.

Yeah do it yourself if you can. $235 at the dealer. Covered under the maintenance plan though, if you have it

Didn't buy the maintenance plan...couldn't rationalize the cost they quoted me for it.

It sounds easy enough, unfortunately I don't have the tools for something like that. Hopefully I can find a friend in the Denver area or an independent shop that won't charge an astronomical price.

Wont cost that much in tools to be honest, and once you have the tools you can change then yourself forever . All you need is an extension for the wrench, the special socket and a wrench+torque wrench, and ideally some anti-seize compound which you can use in many other things. that'll cost around 120$ tops all together, add the sparkplugs, and you're still way below 200$, and you have the tools to do it every time and use for other things aswell.

I'm wondering the same thing because I don't see anything on their website.

Sounds like a swap mod.