I have a 2002 cooper s with about 176xxx miles. Sometimes I notice a hesitation during acceleration (around 2000 - 4000 rpm) and erratic idling every once in a while. Ive read about people replacing spark plugs to fix this so I decided to take out my spark plugs and see how they looked. Immediately I noticed that they were very uniformly black.

Im not sure but Im guessing this shows the car might be running a bit rich? Also I do drive mainly just around town (with lots of stop signs) and usually for short bits of time.

What do you think?
Note: the spark plugs in the pictures are arranged 4 3 2 1
I did scrape the #1 plug

Thanks a lot for any insight

 

They look fairly normal actually. They do look like it is time for a change. I recently had hesitation as well and put some new ones in on my 06. You will notice a huge difference...

How many miles on those plugs?

 

Im not sure (I bought the car only 3 months ago), although I am guessing they are pretty old

 

Yeah, then swap them and you should notice a difference.

 

Thanks for your insight daflake, i plan on getting colder jcw plugs when I get my WMW pulley package

 

I'd go with the NGK Iridium (one step colder) rather than the JCW. I have been running those plugs for a few years now and they are great.

 

If you go iridium, the NGK would be my choice. They have lasted me at least 3x as long as the Denso's. The Denso's were burned down to nubs in about 20k!

 

To get a really good plug check, the engine should be at operating temperature and a clean cut (WOT under load and shut off) executed. It does show that you drive the car as described as the core shows a nice tan color but the tips are black. New plugs should help but I would really consider the same heat range given your driving habits, colder plugs are better for higher speed driving. Warmer plugs are better for stop adn go driving and will fire off better if a lot of cold starts are typical. Colder plugs will foul easier.

 

I believe you have normal wear on your plugs. Our Brisk plugs are on sale right now and are a good choice for daily driving duties and track use. We have not seen an issues with 1 step colder plug fouling in the MINIs but Dw1 you are correct the colder you go the easier they foul.

R53 spark plug sale http://www.sneed4speed.com/mini-copp...sign-set-of-4/ use coupon code briskplugs to get 10.00 off and they have free shipping

 

There have been issues of Brisk plugs breaking in the head though. Also lots of talk of poor performance and blowouts.

https://www.northamericanmotoring.co...essions-7.html

 

What he said ^.

 

Brisk plugs will never see my mini again, I have a brand new set in my toolbox that will collect dust. I will only use NGK.

 

What happened if you don't mind me asking?

 

Littleone 231, what happen with your Brisk plugs? We have a very direct relationship with Brisk factory and would like to know if there is a problem, so we can fix it.

Daflake, the plugs coming out of R53 heads has nothing to do with the plug but poor casting around the plug hole. Mostly #2 cylinder where on some heads there is an air pocket close to the plug hole. We have fixed several of these spark plug blow outs with all different kinds of plugs installed, including stock ones. If Brisk plugs were the issue we would have stop using/selling them years ago.

 

That is what that thread was about. The issues I have seen directly with Brisk (2 MINIs) involved them breaking apart in the head and causing some serious damage. Sorry, I still don't recommend them nor do I believe the HP claim you made. Add that to the cost and my recommendation is still for NGK.

Maybe I am being hard on Brisk as this was a few years back but it was enough for me to lose interest in the company.

 

I understand. As for the HP claims, I test things for mine and our customer race cars so that we will have the best equipment to win races. I share this info so that other people can benefit. I'm current getting all the test data uploaded to our site under "Free Stuff". Currently only the wind tunnel data is up but I have lots of dyno graphs to upload tomorrow.

 

Feel free to post it up, but you can get a 1 -2 variation on a dyno run back to back. Still ain't buying it.

 

Dyno run to run variation is true, and was taken into account. Believe what you wish.