N54 Infamous Cylinder 5 timing corrections with IJE0S and 6HP21

[Vtecnet]

Hey all,

Seems that maybe IJE0S (MSD81) and the ZF 6HP21 are prone to this cyl5 correction issue once you increase power to a certain level?
Now the important thing is, my car runs great, if I didn't look at the logs I'd think all was good.

Just interested to know if there is a fix for this, as my assumption is it'll be costing me top end power?

The car is an E82 135i with 17T turbos, stock DI (Upgraded LPFP) all the usual bolt ons, charge pipe meth 1000ml with 85/15 ratio.
All new injectors, new HPFP, B58 Coils, clean intake ports, all maintenance up to date.
My pump gas is 101.5ron which allows me to make good power without ethanol.

Reducing ignition timing doesn't seems to solve the issue, so I don't think it is octane related, it is adding more boost that really triggers it.
On the lower power Pump Gas only maps all looks perfect with no corrections, however this group only allows me to add one Graph.

26PSI Meth Log:

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16PSI Log: https://datazap.me/u/charlesb/135i-...-9-10-11-15-16-21-22-23-25-28-29-30&zoom=0-61

 

[seb.apprenti]

Hi my friend. I have exactly the same problem as you: map 23/24 PSI Hydra hp800 gen2 sp95 (EUR) methanol port 7 nozzles 6x250cc + 1,640cc ....100% meth b58 coil kit recent injectors index 12 walbro 450 very recent high pressure pump.. I have huge corrections on cylinder 5. my engine compressions are correct and so is the leak rate. I'm lost...I don't know what to do anymore.. did you find a solution to this problem?

 

[Vtecnet]

Hi my friend. I have exactly the same problem as you: map 23/24 PSI Hydra hp800 gen2 sp95 (EUR) methanol port 7 nozzles 6x250cc + 1,640cc ....100% meth b58 coil kit recent injectors index 12 walbro 450 very recent high pressure pump.. I have huge corrections on cylinder 5. my engine compressions are correct and so is the leak rate. I'm lost...I don't know what to do anymore.. did you find a solution to this problem?

Unfortunately not solved.
I have a port meth kit coming, as I thought perhaps uneven distribution with charge pipe meth was an issue, but there's a good chance it won't help, my car has new index 12s and hpfp.

I also broke my diff yesterday, so might be a little while before I can do more testing, got any logs I can see?

 

[seb.apprenti]

Unfortunately not solved.
I have a port meth kit coming, as I thought perhaps uneven distribution with charge pipe meth was an issue, but there's a good chance it won't help, my car has new index 12s and hpfp.

I also broke my diff yesterday, so might be a little while before I can do more testing, got any logs I can see?

unfortunately the methanol injection port does not change the problem. I even tried different nozzles, increasing the pressure of the meth pump... I also tried another index 12... but the same. This subject has been discussed for many years on the forums but I have not found a real solution. I hope your car gets back on the road soon and you find a solution to this problem.

 

[keithkk1000]

Try desensitize knock sensors in MHD setup, it help my corrections.

 

[wheela]

Try desensitize knock sensors in MHD setup, it help my corrections.

Do you have a built engine? I believe this feature is for built engine people with false knock due to the upgrade (I think it's mostly due to closed deck mod). Even if cylinder 5 is false knock for some reason, the risk with desensitizing the knock settings is if you ever get real knock your DME may not detect it so it won't pull timing to protect your engine.

I wouldn't recommend this unless you have really good objective evidence that your modifications have changed the engine harmonics in a manner that the factory settings are no longer valid, and are truly reacting to engine noise that isn't actually knock. Otherwise you're risking your engine.

 

[Keith1k]

Fully build engine, was getting correction at wot shift.
If your car is running well it should be no issue. It will still pickup anything major.

 

[pbondar]

We’ve seen a cylinder 6 misfire at 5k-6k on ‘normal’ engines when pushing around 550 BHP crank…the DMFW is suspected to be the cause..not proved..yet..

 

[SLOWESTN54]

We’ve seen a cylinder 6 misfire at 5k-6k on ‘normal’ engines when pushing around 550 BHP crank…the DMFW is suspected to be the cause..not proved..yet..

I think this is proven. Way back when my car was tuned by V8bait, he had to desensitize knock tables until installed a twin disk with a single mass flywheel. That fixed the issue.

 

[SLOWESTN54]

We’ve seen a cylinder 6 misfire at 5k-6k on ‘normal’ engines when pushing around 550 BHP crank…the DMFW is suspected to be the cause..not proved..yet..

Went back and Confirmed, it was cylinder 6 misfires. And they Went away after the smfw

 

[wheela]

We’ve seen a cylinder 6 misfire at 5k-6k on ‘normal’ engines when pushing around 550 BHP crank…the DMFW is suspected to be the cause..not proved..yet..

Timing corrections and misfires are different though. OP didn't mention having any issues with misfires.

 

[pbondar]

Timing corrections and misfires are different though. OP didn't mention having any issues with misfires.

Ah point taken..

 

[pbondar]

I think this is proven. Way back when my car was tuned by V8bait, he had to desensitize knock tables until installed a twin disk with a single mass flywheel. That fixed the issue.

I meant in my case not proven as I’ve yet to fit my M3/M4 DMFW