His is a weird issue and we have yet to hear if he even changed the wires.

For 99% of everyone else, the 15 or 17% is a safe upgrade. The ECU does not need to be tuned (especially on the 15) but you will get more out of it if you do. The ECU map on a JCW is different over the stock Cooper S.

 

Literly THOUSANDS IF NOT TENS OF THOUSANDS of S mini's have gotten a 15% or 17% pulley...no issues.19%...was an issue for som, but 15%, and 17% are fine...
And the jcw ran on the first s's till 2005 with stock injector sizes till 2005 when the jcw210 package came out.
sorry to hear that the flash did not solve anything...
If you or a buddy has the tools, a compression check, both dry and wet would help rule out some mechanical isdues, except maybe a hotspot due to a protruding head of metal or headgasket making a hotspot....not sure if that is a real possibility vs low compression, or fuel issue....maybe a few (compressin check will rule out compression issue, wet compression check will give extra info, as will listening to where the air is excasping from...crankcase/exaust/intake) gearheads can give a good next coutse of action...check the fuel rail psi...a few post from folls with mx manuals give the specs in other posts.
_

 

today i changed my aftermarhet wires to msd and also made terminals of the coil like new(with sandpaper) but still the same
i made a little video with the sound that car is making...
at 3500~ rpm..

 

https://www.northamericanmotoring.co...nt-happen.html

I made this thread because I was having the same problems on my 05 MCS after a CAI and 17% install. Check out the video and see if it sounds familiar! I wound up replacing my coil and wires and it totally went away. Hope this helps!

 

coils and wires are new... :( wires just arrived and msd coil is in very good condition(after some good cleaning i ve game them today).
i read in your topic that someone changed spark plugs and the problem gone..i think its time to try this.any opinion what sparks plugs to go for.?

 

NGK Iridium, one step colder.

 

i ve just changed me coil to the oem (old one)
which i ve brushed a little with a dremel
problem became smaller
here are some pics of the msd coil
is there any problem that they became black a the end of them???

 

The JCW has proper injectors and ignition to handle a 14%, it also has a different tune, and the truth is that 90% of these pulley upgrades go off without a hitch. It often occurs that upgrading the boost will expose some weaknesses in your ignition or fuel system. I doubt that it is the ECU, as most cars (including mine) can run 15% or even higher on a stock tune.
As for a choice in spark plugs, I have the JCW plugs in mine to compensate for increased boost and they have treated me great!

Sorry to hear that you are having so many problems with such a simple upgrade though, I know they can be a pain.

 

Also, I dont know if youve tried this, but it may help prevent some of that corrosion. You can buy some electrically conductive lube from autozone. Call me stupid, but I always like to put just a dab on each of the coil prongs to give a little barrier from water damage.

 

i ll do the same from now on after i have seen how much rust they catch..

 

I can't really hear anything on your car. My issue is not something that would be easily heard on a video recording so I didn't even bother.

 

it makes some pauses if you listen carefully.like not giving power

 

If you have true "ping" aka pre ignition then higher grade gas will fix the problem. Find somewhere that sells 100 octane unleaded fuel. Put it in if the noise goes away then you have real "ping". If it doesnt you have a mechanical problem that is making a ping like sound. This could be something as easy as the belt tensioner moving around because the belt is too loose (Note- you should be running a JCW belt with the new pulley) or something as bad as the supercharger going bad. Also check your crank pulley and make sure its not broken.
Now if the ping does go away with the 100 octane you have one of 2 problems, carbon build up or for some reason your ignition timing is too high. To high timing is unlikely but carbon build up in a female car is not. The carbon will be in the combustion camber and on the piston. Injector cleaner with some spirited driving can sometimes remove some carbon but the only way to really remove all the carbon is to clean the head and pistons by removing the head.

 

so if I have a lean AFR from a clogged injector or faulty AFR, then the 100 octane would fix that? I was under the impression that if it was a physical problem in the fuel system, it wouldn't matter what kind of gas I put through it. Since the timing is computer controlled and I have a fresh factory flash on it, I don't think improper timing is possible.

belt is correct for the pulley (Gatorback 4060537)
I did seafoam the engine, which I know isnt perfect but I think eliminates the issue of carbon affecting the compression.

 

Gas wont fix a mechanical problem. If you have a bad injector that typically causes a miss all the time because fuel is reduce all the time not just under high load like pinging. Low fuel pressure from a dieing fuel pump could cause ping. If you have a lean AFR logged you most likely have a fuel pump going bad.
We have had very bad luck with the gator back belts. We only use the JCW belt from MINI
Seafoam fuel additive? Thats what I was talking about with fuel injector cleaner

 

I did seafoam through the PCV and ran redline fuel system cleaner through the fuel system.

Bad luck with gatorback in what way? Causing issues like mine or just in general?

lean AFR could also be cause by the FPR is that correct?

 

We had a gatorback snap on one car causing a lot of damage. I use either Gates or NAPA only and have not had any problems.

I think you are getting off the root of the problem. You say you are pinging but are you positive that is what it is? Could it be hesitation caused by maybe a bad bypass valve or maybe a bad throttle body? Of the two, my guess would be BPV as they go bad over time. On my 06 I have had to replace it already.

I guess what I am trying to say is that we need to stop tossing parts at it and get a better idea of what the problem is. My understanding is that pinging will also generally toss a code and I don't remember you saying there was one so I wonder if it is just hesitation caused by loss of boost.

If you want to test your BPV, you can ziptie it closed and go for a drive to see if you have the same issues. If you don't, then there is your problem. After that I would start looking at other items and eliminating them one at a time.

 

Keep throwing parts at it. Eventually you'll get it.

 

Could be the pax seat. Maybe he should try swapping that out?

 

Putting cleaner though the PCV cleans the engine oiling system and internal parts not the combustion camber and valves heads. The fuel system cleaner cleans the combustion camber and valves.
Most of the time the FPR fails open and causes a richer condition. The bypass valve is a place to look but i'm not sure it will cause ping.

 

It won't, but are we sure what he is having is actually pinging? Not trying to be mean, but there is a possibility that what he thinks he has and what he really has are two different things.

I'd like to get more info before he dumps tons of money trying to chase a ghost.

 

Correct, thats what I was saying about the 100 octane. Its easy and not expensive. Its how we always test for ping here at the shop.

 

Gotcha, I just misunderstood ya.

 

This is why I'm so hesitant to do the same upgrade, even though I lust for more horsepower. It seems that based on what people on here are saying is that the room for error becomes SMALLER when you do a 15% pulley upgrade. Either it will expose a preexisting problem, (as per ZippyNH) or it increase the frequency in which you replace the plugs/wires/coil. Am I interpreting this correctly?

 

Any performance tuning will do this, it is normal. That being said, it is very rare that a problem will show up. His is not a normal problem.