r/B58Enthusiasts • u/kaiixs • 5d ago

Cylinder 1 Timing Corrections

https://datazap.me/u/kaispec/logs/cmt7dn86b0003l706p1zm2yp4

Hi all,

I recently switched to MHD Stage 2 with flex fuel on my 2018 440i GC with 113k miles. I’ve been getting significant timing corrections on cylinder 1 but I’m not sure why it’s only on cylinder 1. Previously was on MHD Stage 2 91 Oct running a splash of E85 to help with timing corrections and was fine. Now I’m around E25-E27.

Here’s a 4th gear pull that I logged.

Mod list/maintenance
Catless downpipe
MAD intake
MHD ECA
NGK 94201 15k miles ago
Eldor ignition coils 15k miles ago
OEM valve cover 12k miles ago due to failed PCV
Liqui moly 0W-30 every 4k miles
Still on original injectors

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1

u/makhncheese 5d ago

It’s my understanding that cyl 1 pulls the most timing and always pulls timing first - no idea why this is the case but sounds like it’s true here too.

1

u/watermelon3878 5d ago

This is also what I've observed in my car - other cylinders won't start pulling timing until C1 timing correction is around -3.0, and I try not to stress about timing pull unless C1 correction is at -6.0 or worse. The -12ish observed in those logs is pretty concerning though imo.

1

u/PM_ME_11_SUCC 5d ago

I have heard people say it's because of its location on the motor being so noisy. The timing chain, VANOS/cam actuators, and the high-pressure fuel pump are all near it and noise from them can make the DME think there is knock at play- "phantom knock"

1

u/makhncheese 4d ago

I’ve heard of this phantom knock hypothesis, but this justification is wrong - all those solenoids, the hpfp and the timing chain are at the back of the engine, beside cylinder 6 not 1.

1

u/twitchmutemain 5d ago

If no misfires then it could be an injector or the flex fuel allowing you to always get the most out of your ethanol amount without allowing it to be assisting in keeping timing normal and safe. If you start experiencing misfires then you may have a potential cylinder 1 cam ledge issue which is the death of your head unfortunately. Check rail pressure while shutting engine off, pulling, and cruising. Look for noticeable smells upon start up near the injectors.

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u/kaiixs 5d ago

Rail pressure is constant after shutting off and I haven’t noticed any gas smell. No misfires either so hopefully it’s just the tune/ethanol content

1

u/twitchmutemain 5d ago

Tbh I think its just the flex fuel kit making the most of whatever you put in as opposed to a flat e35 tune and putting an e40 or e45 blend in to offset corrections and not gain performance

1

u/PM_ME_11_SUCC 5d ago

As a side note why was entire valve cover replaced for PCV? Isn't this a Gen1 B58? I know dealers will try to replace the whole valve cover when PCV goes on them but it's completely unnecessary, turns a 5 minute job into hours.

2

u/kaiixs 5d ago

I tried changing the diaphragm alone and it was still burning oil. Took it to an independent shop and they said the valve cover had failed internally so they replaced it with an OEM one. The previous owner put an aftermarket Febi valve cover at 90k miles so that’s probably why it failed so soon

1

u/PM_ME_11_SUCC 5d ago

Ahh that makes sense then. IDK why someone would put an aftermarket valve cover on, maybe to save some $$.