Super Knock code
- Thread starter SlowE93
- Start date
I first saw the super knock code in October 2018 only on cylinder 6 during a 3rd to 4th pull. No stuttering or anything, just that ding noise and cel stating there is a code. The only thing I’ve changed is the spark plugs and swapped out and coded bank 2 injectors. I haven’t seen the codes reappear as of today. The two things I noticed was cylinder 5 injector was a leaking a bit. All this occurred on 93 oct. Not sure if that’s what fixed it or what but it’s something I check constant for. I’m just scared there might be something called super ultra knock lol.
Thanks for posting. I ordered another index 12 today for cyl 2. Hopefully this resolves it. The strange part is no cel, no gong, no nothing to warn me that I triggered that code. So since I first caught it, I try and run codes after every pull which is just stupid. Then the worst part is, as I already said, only way to see if plugs fixed it was to go WOT again. Was fine for a couple weeks, then it came back. So we will see with index 12. These injectors arent even that old so im fuckn lost and mad as fuck !
FWIW I had this code when I first picked my car up from a shop that did a single turbo install. As soon as I left the shop and I pulled on the highway it would throw this code randomly when accelerating under load ~3k without down shifting. It never went into limp mode and I could clear it immediately via MHD. It would only come back randomly under the same conditions I described. I suspected bad fuel and wouldn't be surprised if the shit shop I used put 87 in it. The car was disaster all around when I got the car but this addressing this code was first on my list for obvious reasons. I put fresh tank of 93 and topped with a gallon of 100 octane as the car sat for 6 months. The code did not came back after the new gas. I do need to say I also installed new plugs, coils, HPFP, and stage 2 LPFP a few days after the new gas so the problem could have been ignition or fuel related. I still have not had that code return after several months and many pulls.
I think my issue was octane and I suspect fueling might be your issue due to high rpm setting the code but there are better experts here than me to help figure this one out. Not sure any of this is useful for you but i figured I would post as this code is bit concerning to deal with. Especially when you need to recreate it so many times with logs and fixes trying to figure out what it is.
One question I have is if it doesn't occur at 27 PSI and does at 25 PSI I am assuming you are using 2 different flash tunes, if the tunes are different, is the there a problem with the 25 PSI tune itself.
I think my issue was octane and I suspect fueling might be your issue due to high rpm setting the code but there are better experts here than me to help figure this one out. Not sure any of this is useful for you but i figured I would post as this code is bit concerning to deal with. Especially when you need to recreate it so many times with logs and fixes trying to figure out what it is.
One question I have is if it doesn't occur at 27 PSI and does at 25 PSI I am assuming you are using 2 different flash tunes, if the tunes are different, is the there a problem with the 25 PSI tune itself.
Fuel is NOT the problem. Tune is the same. I believe it only has happened at 25 psi because its what I usually run. For all I know, if I keep the car at 27 it will most likely do it as well. Or even at 23 for that matter as long as I leave it there long enough. The reason I even mentioned 27 psi is becaise I did not believe it was fuel related. If it were, it should trigger the code even more so at higher boost , which it did not. Another thing the lead me to believe its not fuel is why only cyl 2 ? If it were fuel, it would / should, jump around different cylinders and occur at higher psi. Thank for all the guys that have posted. I really want to get this figured out. Hoping its the injector as really, thats all thats left . What I would like to know is, if it is in fact injector, what exactly is happening at above 6k rpm that would cause this randomly ???
A
Are you on stock coils. If not, maybe switch to Precision Raceworks coils and gap at .022
I had BL coils and they ran great from .022 thru .030, then replaced them with PR coils and used .022 and I notice the car is even more silky smooth and responsive, linear. I mean like noticeable quieter and smoother... when switching to e85 same thing although less so than 93.
Are you on stock coils. If not, maybe switch to Precision Raceworks coils and gap at .022
I had BL coils and they ran great from .022 thru .030, then replaced them with PR coils and used .022 and I notice the car is even more silky smooth and responsive, linear. I mean like noticeable quieter and smoother... when switching to e85 same thing although less so than 93.
Are you able to do leak down test and pressure test each cylinder?
The worry with these cars on high boost for a while with an open deck design can be cylinder warping, cracking or the head lifting. Any of these things could really screw up the combustion process.
The worry with these cars on high boost for a while with an open deck design can be cylinder warping, cracking or the head lifting. Any of these things could really screw up the combustion process.
Appreciate the response. R8 coils and Delphi do the same. As I said, car was fine, this just started.
I don't think stock turbo maxed out boost levels could approach warping stock cylinders... if the user had upgraded turbos AND was pushing beyond 650 whp... then that would be possible.
If the injector doesnt fix it, I will go to my storage and dig for my gauges. I dont think thats the issue though. Usually when something like that happens, you can replicate it almost everytime and are other signs as well. Here is a log weeks AFTER the code appeared. Generally when you have issues in the cylinder itself, you get misfires, oil consumptuon, smoking, poor timing, etc. and will replicate the issues under the same condition, boost, gear, weather, etc. Not the case here.
As stated before. Depending on boost im between 580 whp to 600whp. But as I said, I dont believe that to be the issue as I would not be able to pull clean logs , no smoking, car is SMOOTH , no misfires, etc
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You wouldn't think so but it's possible. There is an old post on another forum of a guy on stock turbos who cracked a cylinder. The car ran without any codes.
Possible reasons for the crack were thought to be either a defect in the block, overheating (i.e. water pump failed and car ran hot. Possibly bits of old pump blocked the coolant from flowing) or a head that was put back on wrong. That is, it wasn't completely flat and torqued down correctly, allowing for some movement of the cylinder. There's also a different case of a piston splitting in 2. Also on stock turbos I believe.
some pictures from those threads below:
so yeah these failures are rare but it's worth doing something like a compression test to see that everything is sound with the cylinders.
i myself ran my car at 23 psi on stock turbos for about 2 years and now i'm running 25psi on gc turbos for about 2.5 years.
luckily all seems good. it's quite alot more than the stock 8 psi the car was designed for. I know the N54 was over engineered as a turbo test bed before the m3/m4.
Obviously if the car was messed with, then anything is possible to go wrong. We talking about an unmolested car with zero questions about maintenance or repair scenarios.
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I believe it is going to be the injector. Car has been parked since it threw the code and I ordered another index 12. Since it was not the plugs, I decided to swap back my only 6 week old NGKs. #1, no issues, #2 as soon as I loosened it, it was already smelling. Pulled the plug out and it reeked of corn fuel. Dry, but the smell filled the garage. All others came out normal. When I swapped plugs last after it threw the code a 2nd time, the car was ran, let cool, and I swapped plugs with my old spares. So didnt sit long enough and there was no obvious smell. Index 12 gets here today so hopefully this solves my problem. For sure #2 is leaking though. Who would have thought an index 12 would go bad in a little over a year, yet my index 9s were fine before I upgraded to index 12 and we're in the car for 9 years.
Thanks. I will update the thread as it may help someone else going through the same thing. I just want to know what the scenario would be that a leaky injector would cause a super knock code. I know for sure its the DI injector as I got the code(s) with 2 sets of pi injectors (upgraded from 550 to 750). It sucks that its a shadow code and does NOT alert me when it actually happens although the last time it happened, I felt it. It seemed like anti lag was triggered and I immediately let off. Pulled over, checked codes and found the 30EE.
Wow, hopefully it works out for you. I had the same issue. I just parked my car and its been sitting ever since lol . Too lazy and annoyed to throw random parts at it until the problem goes away.
Yeah, these cars become money pits QUICK ! One thing I have learned, if it aint broke, dont fix it. As I said, my index 9 are still good sitting in a box. Swapped to index 12 and a year later....here we are.
