My 05 S is pinging (I can hear it) at anything above 4K RPM and 2/3rd's throttle. 15% pulley, CAI, One ball exhaust, Cooler plugs. Its not consistant sometimes worse than others. I am thinking its lean and I know its not ignition related. Any sugestions

 

Are you familiar with pinging? If you're not sure, I'd tend to think it is something else; exhaust rattles, for example, can mimic pinging pretty well. The car has knock sensors so you shouldn't be able to hear consistent pinging if the knock sensor is working. Perhaps it is not.

- Mark

 

I understand. 26+ years as mechanic, motorcycle and aircraft. Its definitly pinging and sometimes you can actualy feel the timing back off to try and stop it.

 

that tend to show up eventually for many. And it's not because of running lean, it's from a long time running rich! For a lot, it's from carbon build up creating hot spots OR from your plugs going south....

Change your plugs and see if it gets better. If not, run some stuff like SeaFoam through your intake system.. and through the tank.. Instructions are on the bottle. Others use Techron or BK products.

I had the same issue and the Sea Foam really, really helped me.

Matt

 

I am on my second bottle of Techron and it has improved slightly. I just hate pouring aditives of any kind in my car. Your idea of running rich could be right on the mark. I know its fuel related.

 

get rid of the pulley and it will go away

 

Nope, it did it before any mods were made as well.

 

It also could be the knock sensor.
Replace and see if it improves.

Pat

 

do the plugs. It's cheap and easy, and many, many a MCS owner has had the same symptoms and either the cleaner or the plugs have made it go away.

If you do the Techron/Sea-Foam stuff, don't just do it through the tank. Suck it into the intake track, let it soak, and then run the car to get the stuff out.

Old school used water to decarbonize as well.

The knock sensor it a good guess too, but timing pull related knock onset is the only kind that control loop can effect. If it's from carbon induced hot spots or bad plugs, then there's nothing that the ignition loop can do, cause it's not the cause.

Matt

 

Find the solution before you burn a piston, as in my case...I tried plugs, seafoam, and what did work was 100 octane race fuel (however very expensive)...good luck.

 

well; if you're a mechanic you've already hit the block with a hammer to see if sensors working .... so the seafoam in the big grey vacuum line at 2000 rpms should help . but use caution these cars hydro lock easily so i'd do it with a very warmed up engine .; intake and all . just so it vaporises good . i haven't pinged ever since adding an oil cooler .

 

Had the exact same issue, nothing but 100 octane fuel helped, I tried EVERYTHING, put on a stock pulley again, now car feels like it has more power than with a 15% pulley. Timing is not being retarded to such a degree.

 

RMW tune fixed mine.

 

i was just gonna say......maybe a proper tune might help solve the issue. I'm sure Jan could probably clear it up by adjusting your values.......give him a call see what he thinks. You'd be surprised how much he can help over the phone.

Steve

 

I see several of you folks use 100 octane fuel. Is this just an additive or are you sourcing it from some special place? Most fuels around here are only 91 octane.

Pat

 

Thanks everyone for all the sugestions. 100 octane is out of the question for a daily driver. The knock sensor system on the mini is a detonation counter so hitting the engine block with a hammer wont work. I have a couple emails out to M7 and Mini Corsa so we will see what they say. Only severe detonation will hole a piston, most detonation eats the crown away just above the ring until you loose the ring. mine is not even close to being that bad. Looked down the plug holes and the piston crowns look fine. I am thinking about borrowing the bore scope from work to have a look at the entire crown.

 

it seems that more and more fuel distributers are adding more and more ethanol ( alcohol ) into the fuel blends. During seasonal fuel changes the additive packages in the fuel changes and sometimes can result in a poor mixture. Im not saying this IS your issue, im just adding my input. BMW recommends a maximum alcohol content of 10% or you may develop knock,running issues, starting issues, all of the above. im sure it goes without saying but make sure you are running atleast 91 octane from a "top tier" fuel distributer such as Shell,Chevron etc.

 

I agree with the top tier gasoline idea. I only buy fuel at Chevron. I have to run premium grade in my goat as well and in 4 years have never had a problem. My wife as well only purchases fuel from Chevron and though she doesn't have many mile on her mini we have had zero problems to date.

Pat

 

The whole top-tier thing is mostly a marketing ploy, similar to the sticker under the hood of the MINI that says what brand of oil they recommend. It's true that you can get "bad" gasoline but one blend of additives (and their all remarkably similar) doesn't decrease that likelihood. Since around here Phillips 66 consistently had 93 Octane I typically buy from them but overall I have no issues with buying fuel from any modern station that looks to be in good repair as long as they have at least 91 octane (the local Hucks/Amoco station has premium that's only 90 octane).
Also, ethanol itself will not induce knock as Ethanol is an octane booster (E85 is 106 octane) and most fuels sold in the US, regardless of brand, or 10% ethanol for emissions reasons since Ethanol burns cleaner than pure gasoline.

 

Have always ran Shell 91.

 

I agree and disagree. True that ethanol is an "octane booster", but what is octane? The designation "octane" on gasolines is not what you might think. As you
know, octane is a hydrocarbon with the formula C8H18. You also know that this is not the same thing as ethanol.
Virtually all petrol stations offer a variety of fuels with different Octane ratings, and the numbers usually range between the high 80s and the mid 90s. This number is the resistance of the fuel to self-igniting.
This number is based on the behaviour of a mixture of Octane and Heptane which is the other major component of standard fuel. For example, a mixture of 90% Octane and 10% Heptane has a standard resistance to spontaneously bursting into flame. That resistance is given the value "90". If the amount of Octane is increased to 95% and the Heptane reduced to 5%, the resistance of the fuel is rated as "95".
This effectively means that the rating of petrol is a good guide to the percentage of Octane in it. However this is not always the case. Fuels may contain other chemicals but as long as the overall mixture has the same resistance to self igniting as, say, the 90/10 mix of Octane/Heptane, that fuel can be labeled "90" Octane rating.
Now here is the Important part. ETHANOL HAS LESS ENERGY than gasoline. approximately 34% less per unit volume. With less energy and higher combustion chamber pressures and temperatures and the fact that our minis run "pig rich" with a poor air/fuel mixture the possibility of knock becomes a real factor with this crap we call american gasoline.
I agree that "top tier" is a ploy due to Texaco giving BMW money to begin racing back in the early days ( hence the ///M logo ) but i have personally seen what crappy gas can do to a BMW engine. I deal with it almost every day. You may certainly have other issues going on but dont be so fast to say all gas is the same because its not.

 

At all RPM's ? Or do they lean out as RPM's rise and throttle openings increase?

 

runs very, very rich so that the extra fuel keeps the combustion chamber temps down. Think of it as water injection with gas instead of water. It's a common technique to keep detonation at bay. Look around for A/F charts and you'll see at WOT that it runs rich at all RPM, only starting to get less rich towards redline where the stock injectors are starting to get maxed out.

At less than full throttle it's all moot because the engine is running at so much less than full capabilities.

Matt

 

Dr. Obnxs never fails to explain things perfectly i think

 

how could that be? i have a 15% and experience no pinging