Let me start off by saying that I have never put less than 93 octane Top Tier fuel in my MCS. I am running a Stage I ALTA tune and have had the BSH catch can and port block off for the last 4,000+ miles , and yesterday I was cruising in 4th gear around 50 or so mph when a stop light ahead of me turned yellow. Instead of down shifting to 3rd gear and stepping on it, I proceeded to get into the gas just a little bit (I didn’t lay into it). Apparently that was still enough where the programming did not like the throttle position and I experienced the Superknock. The car hesitated a bit and then picked up as normal. This was very casual and non-chalant. I am very, very surprised at how easy it is to experience this condition! So, when I got home I pulled out my AP and checked the codes and had the two superknock codes, which I cleared. The car then ran beautifully as I took it out for a spirited run. No subsequent codes.

So I really have only one concern which is…are the superknock codes stored deep into the soul of the ECU so that the dealer could question fuel quality or anything else for that matter? I can’t imagine that would be the case. The superknock did not induce any sort of CEL so I am thinking that there a ton of people that have those codes stored if they don’t have the ability to clear them. Also, because It’s a “soft” error if you will, does it still put the car in some form of limp mode? The reason that I ask is because it appeared that the car ran much better after I cleared the 2 codes. Not sure if it was placebo or not.

Anyhow, it left me sort of scratching my head how easy it was for this to occur. I would think with the programming technology of today…I low load, high throttle position condition should easily be programmed to avoid knock altogether.

 

Welcome to the joys of a R56.

The superknock code is almost unavoidable. Doesn't matter if the car is stock, tuned, highly modded...they all do it.

I think once you clear it with the AP, it will no longer be stored. The superknock is a DME code and will not trigger a CEL. They are usually stored until they are cleared, so like you said, I'd bet a big majority of R56 owners have no clue that they have a superknock code. Something like a scan gauge won't even pull them....

 

What is this Superknock exactly?

 

I am not certain, but (correct me if I am wrong) it may be what is called "bogging" as in when you give it gas in too low of a gear. Reading the post above it seems this may be what it is noticing. A downshift may have avoided it, but a little bog now and then isn't going to amount to much in the long haul.

 

So the other morning i was in 4th at like 20mph and stepped on it. The car stumbled and flashed a CEL. I got off the gas, the cel went a way and got back on the gas and the car ran fine..

is this similar?

 

It's a severe instance of engine knock/detonation.

It is usually audible (pinging), and you can feel the car stumble as it happens...

 

John.. I just had this issue, but only on the first hard acceleration after a cold start (even with car warmed up fully, as always). Accelerate, then hesitation with a few pops out the back sometimes smoke, and sometimes clicking(ratcheting) in the engine..

Try sea foam. This solved my issue after 2 weeks with the issue, now 2 weeks and no problems.

Tried new plugs no change.

 

Mine would do the same...always on the first hard acceleration after a cold start (after being up to proper temp...)

 

Hey guys. Yeah....forgot to mention the audible knock associated with my intial post. Hence....the term superknock.

HRM,
Lugging or bogging the engine is a term that I am familiar with but usually lugging the engine is a condition of high throttle position and low RPM. I was only into the throttle a little bit. On my M3, I have tuned the map by hand to allow me to mash the throttle at low RPM with minimal stumble and no knock and this was technology of the 90's and that is why I am so surprised by the fact that superknock was so easy to experience on a car built last year!

Atleast I fell a bit better know.

Erik -- Chevron Techron'd the car prior to my last oil change. I can't imagine that I would have much carbon buildup after 6,600 miles???

 

You'd be surprised. Especially running higher boost. Pull your plug (14mm deep 12pt socket) and look at the piston, or pull your intake mani and see if there's any bad build up. I completely jinxed myself, and experienced it again this morning, ugh. I may need to pull the intake mani and manually scrub, I don't thin the sea foam is strong enough at this point, as it's likely caked on (1st treatment was last may, prob 35k miles, now at 52k.) If you do it at intervals of 5 or 10 I'm sure things would be a lot better in the long run.

 

There is no way I am doing that kind of maintenance on this car if that's what is required. I'll buy an e28 5 series or an e30 325is and drive it's doors off as a daily before I start scrubbing intake manifolds or changing out plugs after a mere 6K miles. That is just absurd!

 

I did a little bit of reading about superknock. Two things that struck me were some theories about it being caused by improper tunes or possibly by problems with the EGR systems. Seems like both of these might apply in this case. Something to think about.

 

Thanks for taking the time to share. From what I have read, it seems that superknock is encountered by all walks though. Totally stock, tuned, EGR modified, EGR not modified. It is certainly something to look at though.

 

Water/ Meth injection should solve the problem.

 

You sure about it being common if stock? I suspect it is not common at all on stock cars.

 

I was just saying pull the plugs to gain access to look at the pistons for evidence of carbon b.u. Def don't need to be changed this early. And I agree with you anyways, which is why I've contemplated selling my car half a dozen times already.

 

Yes.

Again though, I bet 99% of them have no clue their car has a stored code, because you cannot see it (even with a scan guage). And unlike us discerning drivers, that notice everything....the majority of mini owners buy them because they are "Cute"...and I could see them being completely oblivious to a single instance of the superknock.

The techs at my service dept said, literally all of the cooper S's come in at some point with superknock faults stored. I'm sure being in AZ with 110+ summer temps and crap 91 octane doesn't help...but I believe it.

+1000 I miss my R53 everyday.....but I know if I went back I'd miss my torrrrque.

 

hmm.. the only time i've ever had superknock was when I had the UNICHIP installed.

 

In case it hasnt been stated. superkock is knock that can not be removed with timing retard.

 

Thank you. I didn't know what was being discussed but have experienced it a few times now. I just assumed it was heat related and backed out of the throttle every time I've heard anything remotely sounding like a ping. I guess a trip to the dealer is in the cards.
Thanks

 

Mine does "superknock" bone stock with 2000 miles on it. "Top tier" gas, grocery store gas, none of it makes a difference. Always "premium" of course. Mine will do this occasionally when going up a steep hill and giving it a little gas. The car will ping audibly and bog badly. It seems less prone in "sport mode" because the auto is real responsive and downshifts instantly.

I seem to have a solution to this finally in the past 2 weeks though, and that is to dump ~12 oz of Torco Accelerator into the tank when I fill up. Its not "octane boost", but highly concentrated very high octane race gas. I've used it in the past on modified forced induction cars with no ill effects and great knock prevention. This blend is yielding probably around 94~ octane when added to the 91 I get around here. The car runs really well and I can't get it to ping anymore. I'm happy to have found a fix, but by the same token, having to jack the octane up THAT high on a stock brand new car is nothing short of repugnant BS. Not to mention the $6 bucks worth of stuff I have to chase $50 tanks of gas with. Its a fun car, but as soon as the warranty is within 6 months of gone, bye bye.

I called the dealer a few weeks ago and described the behavior, then asked if there were any ECU re-flashes available. The dealer said no TSBs at all on my 2011, and even agreed that if I didn't think they'd be able to easily recreate the issue, then chances are they'd do nothing about it. This is when I ordered the Torco...

 

The best way to avoid this is to ensure that you are at 3,000 RPM or so going up any hill so.....drop the hammer.

 

Yep I've noticed the same thing. I live at 7700' feet of elevation in the mountains though, so driving up hills is a frequent thing and I'd be nailing it constantly. I've taken to driving around in sport mode unless I get down to Denver and I'm just cruising around where its relatively flat. That seems to eliminate the chances of it happening, and now with the Torco it hasn't happened in a few weeks...

 

Had something similar to this happen to me the other day. Gettin' on the highway, mashing the gas in 4th @ lower RPMs, gave a chug and a noise I've not heard before. Thanks for the input, folks; might have to run by the dealer sometime soon!

 

If anyone actually has the dealer DO anything about this, please be sure to post back here! I determined with a service advisor that they weren't going to do anything so I never brought it in. The Torco Accelerator is working for now by just raising the octane up to 94-96, but I'm hoping MINI will come up with a fix some day.