[Bimmer 808]

It's been a while since I checked my codes, but when I did it showed super knock codes 30F0 and 30ED on cylinder's 1 and 4 respectively. I never experienced engine problems or loss of power so I'm not sure if my engine actually experienced the event or if it was caught and prevented beforehand.

I conducted a compression test and all cylinders came back 150ish so I think no engine damage was sustained if it happened.

Not a lot of info on super knock out there. From what I've read it happens during low speed/high load conditions, and when it does occur it can be really bad.

Anyone have experience with this?

[RCOLEMAN545]

I actually had the same code (30ED) when I checked my DTCs the other day. I was lugging my car in boost on the interstate and it felt like it lost all power and shook pretty badly. After that, it was fine. It was pretty hot out that day, i'm not sure if being hot out, and octane quality was the culprit.

What tune are you running?

What fuel is currently in the tank?

How much ethanol is currently showing up on your gauge?

Etc.

[Jeff@TopGearSolutions]

How old/what revision on the HPHP and injectors?

[Bimmer 808]

Originally Posted by FCobra94

What tune are you running?

What fuel is currently in the tank?

How much ethanol is currently showing up on your gauge?

Etc.

Running an E60 tune, when the event happened I was probably around E50.

Current gauge shows E57.

[Bimmer 808]

Originally Posted by Jeff@TopGearSolutions

How old/what revision on the HPHP and injectors?

HPFP was replaced under warranty in 2012. Injectors are index 11.

I cleared the codes and they have not shown up since. You think it's an injector coding issue?

[RCOLEMAN545]

Originally Posted by Bimmer 808

HPFP was replaced under warranty in 2012. Injectors are index 11.

I cleared the codes and they have not shown up since. You think it's an injector coding issue?

Did you ever get anywhere with this? I got a 30F0 on the way home last night. Once again, interstate speeds, just rolling into the throttle.

[Bimmer 808]

Originally Posted by RCOLEMAN545

Did you ever get anywhere with this? I got a 30F0 on the way home last night. Once again, interstate speeds, just rolling into the throttle.

Never found out what the cause was. Codes never came back. Thinking it probably happened when I was at No Fly Zone doing back to back runs and IATs hitting 180. Plugs and coils are new, oil changes every 3-5K. Engine is still smooth like butter and boosts to 21 psi without issue. Guessing there isn't a lot of experience with this in the community (yet) based on the lack of response. I did add this subject to key words so people can search in the future.

Did you conduct a compression test?

[RCOLEMAN545]

Originally Posted by Bimmer 808

Never found out what the cause was. Codes never came back. Thinking it probably happened when I was at No Fly Zone doing back to back runs and IATs hitting 180. Plugs and coils are new, oil changes every 3-5K. Engine is still smooth like butter and boosts to 21 psi without issue. Guessing there isn't a lot of experience with this in the community (yet) based on the lack of response. I did add this subject to key words so people can search in the future.

Did you conduct a compression test?

Not yet. I am in the middle of cleaning the intake ports, will do a compression test at the same time. I'm thinking mine is a fuel issue. I flashed the 91 octane map and had no issues. The issue came back once I switched back to the 93 map. I normally get gas from the same place, it's 93 with up to 10% ethanol. I think the map is too aggressive for the watered down 93 that is in the pumps this time of the year. I would add a few gallons of E85, but my LPFP is dipping into the high 40s with straight 93. After I replace the fuel pump, and get a few other odds and ends done, I will report back.

[FamilyManTrackSedan]

How bout since then

[ArcticRik]

I also am getting slight stuttering when WOT from 20mph. Brand new LPFP, coils and spark plugs.
I noticed the codes-
30ED - Superknocking cylinder 1
30EF - Superknocking cylinder 3

Any update? I have switched to stock map on MHD. I was Stage 1 when the codes popped up.

[RSL]

Originally Posted by ArcticRik

I also am getting slight stuttering when WOT from 20mph. Brand new LPFP, coils and spark plugs.
I noticed the codes-
30ED - Superknocking cylinder 1
30EF - Superknocking cylinder 3

Any update? I have switched to stock map on MHD. I was Stage 1 when the codes popped up.

Patient: "Doc, it hurts when I do this."
Doctor: "Stop doing that."

Super knock occurs in high load, low RPM situations on forced induction DI motors. There are multiple injection events to help avoid it, but it only reduces the chances, doesn't eliminate them. It can and will make a mess of cylinders/motors. Choose an appropriate speed for the gear, gear for the speed or change your turbos to something that spool slower.

[rosullivan04]

Super knock is serious, get your car looked at immediately. Could be old/leaky injectors, HPFP etc. It doesn’t take but a few times for super knock to bend rods, esp. if you’re modded.

[mfish123]

I had this issue when I started running ethanol on relatively new OEM plugs. I switched to the NGK plugs (properly gapped) and after that did not get any more Super knock codes

[Tangent]

I had one of these codes pop up a couple of times shortly before I got a code for a bad O2 sensor. After replacing both sensors I never got any of the codes again.

[DodgeMyCum]

I had a superknock on cyl 1 (30ED) about 5secs in at WOT at 100mph, felt the stutter and let off my foot. It was a warm summerday and my only mod was DPs, running mhd stg 2 on 92oct... no issues so far, but haven't made a compression test yet :O

[Cabdriver]

I had super knock pop up as well twice, got a CEL but did not experience any drivability issues.

I cleared the code and made a slight tweak to the tune - running my own tune. I am FBO (ins/outs, DP, IC, MHD, DCI) - think the tune was a little to aggressive, probably needed to reduce timing in the mid-range, I think it was detected at about 4.3k rpm when I looked at the log. Log didn't show anything out of whack either
I also have all new index 12 injectors and plus only have 5k (ngk's).
Coils are old, they are next on the list - I will be installing meth injection soon to reduce IATs and add octane.

[kingcloudix]

Just experienced the Shadow Code 30EF Superknocking Cylinder 3. Low to hard acceleration. Car paused/bucked then took off.

This is 2 days after replacing Spark Plugs PCV Valve and new Index 12 Injectors. I’m running MHD Stage 2+ 91 octane but I use 93 octane gas. Could this contribute to issue?

I usually run Stage 2+ 93 but Mechanic suggested not to run Stage 2+ 93 as a precaution and for timing.

Should I switch back to 93 map?

SN: All oxygen sensors were replaced 10/2020.

[iqraceworks]

Originally Posted by kingcloudix

Just experienced the Shadow Code 30EF Superknocking Cylinder 3. Low to hard acceleration. Car paused/bucked then took off.

This is 2 days after replacing Spark Plugs PCV Valve and new Index 12 Injectors. I’m running MHD Stage 2+ 91 octane but I use 93 octane gas. Could this contribute to issue?

I usually run Stage 2+ 93 but Mechanic suggested not to run Stage 2+ 93 as a precaution and for timing.

Should I switch back to 93 map?

SN: All oxygen sensors were replaced 10/2020.

If you want to be on the safe side....running 93 fuel with a 91 tune is not a bad idea. Also, run some logs....see if you have lots of timing corrections.

[kingcloudix]

Originally Posted by iqraceworks

If you want to be on the safe side....running 93 fuel with a 91 tune is not a bad idea. Also, run some logs....see if you have lots of timing corrections.

Thanks for that. Was a little hesitant but good to know this is the safe side of things. I’ll keep it that way (91 Tune 93 Octane).

I’ll also pull some logs tomorrow after my emissions test. Not sure what to look for exactly so I’ll post up as well.

[aarongalve]

Originally Posted by Bimmer 808

It's been a while since I checked my codes, but when I did it showed super knock codes 30F0 and 30ED on cylinder's 1 and 4 respectively. I never experienced engine problems or loss of power so I'm not sure if my engine actually experienced the event or if it was caught and prevented beforehand.

I conducted a compression test and all cylinders came back 150ish so I think no engine damage was sustained if it happened.

Not a lot of info on super knock out there. From what I've read it happens during low speed/high load conditions, and when it does occur it can be really bad.

Anyone have experience with this?

Ive have a cylinder 6 superknock code. My engine wouldnt start and it turned out my starter went out too. This was when I tried to put cheap 91oct gas on a normal 91 tune not an ACN91 tune. Which was a bad idea because I'm in Arizona and should be using a ACN91 tune. Towed it back home and pulled everything apart. Cleaned the valves, put new sparkplugs and new coils, new starter and put some octane booster into the crappy gas I put to raise the octane a bit. Car started perfectly and now runs fine. Put in new index 12 injectors and now running stage 2+. The super knocking code never came up again. Might have to try to raise the octane o-o idk

[Tiberius73]

Superknock codes happen when the octane is too low for what the engine is trying to do.

That could be because your fuel really isn't the octane you think it is (for whatever reason) or that your engine is trying something too aggressive.

If you have a well-known OTS tune (MHD, JB4, etc), then this should only (realistically) happen if your fuel is bad (was the car recently sitting for a long time?) or if something is not quite right with your injection/ignition system.

The best thing to do to narrow down the problem is change your tune to a tune for 2 octane levels lower and try to produce the issue again. Usually this occurs when lugging the engine (low revs + boost in manual gearbox as the AT would downshift) and in a car with AT/DCT transmission it typically happens the most at ~4-4.5k rpm.

When you get ANY superknock code you will not get a CEL (unless it's coming together with other codes/issues) but you will see the *little* warning triangle appear in your cluster. Also you might feel the engine hesitate or judder slightly. It won't bong or ding at you, so you have to look/notice. Just the warning triangle will appear and it will disappear ~10 seconds after the issue occurred. If the issue occurs AGAIN within 10 seconds, it will trigger a CEL and limit boost and it will bong/ding at you.

If you are getting superknock, you CANNOT ignore it. You have to either immediately de-tune the car somewhat to prevent it. Superknock codes mostly happen because the DME detects a situation where it knows a major knock event will occur if it doesn't. But it's not 100% successful. You can absolutely bend rods if you think just because it's a shadow code you can deal with it "whenever".
Of course, how good your DME is at intervening in time depends on exactly what's causing it. If it's bad fuel, probably it will be successful almost all of the time.
If an ignition component is bad, then because the timings are out, the DME has more scope to fail. Overall, it's a dumb way to grenade your engine.

Some common reasons to get a superknock code even when your car/engine is okay:
1) Bad fuel/old fuel (octane too low) for current tune, e.g. E60 tune and running E30.
2) Upgraded turbos, e.g. OTS tune from MHD/JB4 with lighter, billet wheel turbos in stock frame (will often produce superknock ~3.5-4k rpm)
3) Intercooler too small combined with hot weather in low-rpm/high-boost mode, e.g. ~2.5k rpm WOT in SoCal/AZ/NM in summer

There can be other reasons, but those 3 pretty much cover the most likely causes.