Super Knock code

[Omar@VaderSolutions]

check for oil contamination in intake runner on head. report back , you could probably use a walnut blasting . might just fix your issue

EDIT: also plugging the head ports would be a great idea. if valve cover is internally cracked it could be causing reversion issues

 

[SlowE93]

check for oil contamination in intake runner on head. report back , you could probably use a walnut blasting . might just fix your issue

If my tuner believes its not hardware or tuning related, I will do that. But last time I pulled the intake, my valves were still clean. I walnut blasted a couple years ago and then added PI so valves stay pretty clean.

 

[Omar@VaderSolutions]

cool i agree pi would keep it clean. but if its not tuning related i would check coils, plugs(again) , injectors, valve cover, and plug headports

 

[SlowE93]

In my log it shows that AFR had a small spike on bank 1 when this happened. Car went into open loop at that time. Trims show this for BOTH banks. Afr 2 maintained target. Afr 1 hit 14.5:1 and 14:1. This is why im waiting on tuners response. I dont know if the open loop is cause (tuning issue), or consequence of the event.

 

[SlowE93]

cool i agree pi would keep it clean. but if its not tuning related i would check coils, plugs(again) , injectors, valve cover, and plug headports

Exactly. Also from my last post, you may think its an 02 issue. No codes for 02s. 02s are not that old. Replaced couple years ago. Also last year , my logs showed the same thing (when I first experienced superknock) and it turned out the index 12 fixed the issue.

 

[Omar@VaderSolutions]

i guess we just wait and see what your tuner says

 

[SlowE93]

i guess we just wait and see what your tuner says

Ordering an index 12 now just in case. Fuck it, I get most of my money back. Ill just eat the over night shipping and the shipping back to them. Ill keep udating this thread in case it can help someone in the future as I did last year / early this year.

 

[jts1981]

U know what cylinder by chance ?

I've had a shadow code 30EE super knock cylinder 2 back in October but we thought it was was related to some fuel cleanser I was using...Since moving off that and back into regular fuel its been fine until a late December. No I am seeing shadow code 30F1 super knock cylinder 5 only.

Unrelated I also had active code 2A7A camshaft position controller, exhaust cold start. This one has been a real bitch since we replaced both vanos numerous times and changed the cam gears. Cam ledges were fine. Car ran fine for months but its just popped up in December along with 3100.

I also have a shadow code 2FDA crankshaft sensor, signal missing. We replaced the sensor in November but its back again.

I have a slow crank on cold start. Could this be the culprit for the 2FDA/ 2A7A?

One thought was super knock was trigger when I drove through a really long, rough patch of shoddy road work while at speed.It was cracked a rear wheel kind of rough road. Could the heavy vibration trigger super knock?

 

[SlowE93]

I've had a shadow code 30EE super knock cylinder 2 back in October but we thought it was was related to some fuel cleanser I was using...Since moving off that and back into regular fuel its been fine until a late December. No I am seeing shadow code 30F1 super knock cylinder 5 only.

Unrelated I also had active code 2A7A camshaft position controller, exhaust cold start. This one has been a real bitch since we replaced both vanos numerous times and changed the cam gears. Cam ledges were fine. Car ran fine for months but its just popped up in December along with 3100.

I also have a shadow code 2FDA crankshaft sensor, signal missing. We replaced the sensor in November but its back again.

I have a slow crank on cold start. Could this be the culprit for the 2FDA/ 2A7A?

One thought was super knock was trigger when I drove through a really long, rough patch of shoddy road work while at speed.It was cracked a rear wheel kind of rough road. Could the heavy vibration trigger super knock?

Have you changed anything on the tuning side ? Whwn most get these codes, lowering boost hides it. Less stress on motor and code goes away. As far as crank sensor, its a funny thing, just recently that code turned into crank sensor for some people. Few months back it was a hpfp code. So now its same code, different description. I contacted MHD about it and they said its tune related. Yet others are experiencing the same thing, on the same tune they have been running for years.
Not sure on a wheel issue triggering superknock, I highly doubt it though.

 

[SlowE93]

Oh, BTW, I replaced crank sensor and I still get that code Never any issues starting the car though , just a shadow code

 

[Omar@VaderSolutions]

that shadow code pops up a lot

 

[SlowE93]

that shadow code pops up a lot

Correct, but it used to be for hpfp. Now it reads crank sensor.

 

[SlowE93]

Check this out.

2FDB changed from one month to another

 

[jts1981]

Have you changed anything on the tuning side ? Whwn most get these codes, lowering boost hides it. Less stress on motor and code goes away. As far as crank sensor, its a funny thing, just recently that code turned into crank sensor for some people. Few months back it was a hpfp code. So now its same code, different description. I contacted MHD about it and they said its tune related. Yet others are experiencing the same thing, on the same tune they have been running for years.
Not sure on a wheel issue triggering superknock, I highly doubt it though.

No change on the tuning side.

 

[SlowE93]

Ok, to answer a couple of pms, swapped the injector. Have yet to drive the car since tuner hasnt got back to me. I may flash my old tune so I can drive my car again and will report back. Only problem with that is, if all is well, we wont know if its the tune or injector that fixed the issue.

 

[MoreBoost]

Do cars generally recover from super knock events?
I got the impression that it was terminal. That the car would never be the same.

 

[SlowE93]

Do cars generally recover from super knock events?
I got the impression that it was terminal. That the car would never be the same.

Yes, they recover, but not all. Its strange as mini coopers suffer from this. Only thing is most other cars that get this code, it happens during low speed, high load.
When many tuned N54s get this, its top end WOT. So root cause may or may not be the same. I have read and watched videos that say engineers and scientists still dont know 100% what causes this phenomenom.

 

[SlowE93]

The Effect of Oil Intrusion on Super Knock in Gasoline Engine

Super knock which occurs in highly boosted spark ignition engines in low speed pre-ignition regime can lead to severe engine damage. However, super knock occurs occasionally, it is difficult to clearly identify the causes. The widely accepted assumption for the cause of this phenomenon is oil intrus

www.sae.org

Oil is a very strong "assumption" that is floating around. Nobody is 100% sure though.

 

[SlowE93]

The problem with the links I posted, superknock codes have been linked to lspi. My car and MOST other N54 members, occurs at high rpm. Either top of rpm range or right after shift. Either way, rpms are up there. I am now looking into api sn plus oils. Once again, for cars that suffer superknock during lspi, but I feel it obviously cant hurt any. I swapped my injector but have only done a few pulls. So far, so good. Problem is, even last year when I experienced superknock, it did it maybe 3 times or so in a month. It was never back to back. I would change, say, the plugs. Run it. All would be ok then out of the blue, I would get superknock. Swap coil, same scenario, after index 12, it didnt come back until the following December. I am thinking weather plays a part as well. What a coincidence that it happens in Dec. / early Jan. and higher boost. Lower boost and many people stop experiencing this issue in the N54. Curious as to others experiences.
1 guy said for sure his tune was causing it as he didnt swap any parts but only the tune and it never came back.
Very curious as to what was different in the tune.

 

[Shahid]

Any update on this I started getting superknock codes as well. FBO with RB turbos..upgraded LPFP, Index 12 injectors. Could this be due to a HPFP that is bad or is going bad?