[X3MCHammer]

Hi all. I have been running the MHD OTS Stage 1 (91 Octane) Map for a few months starting in June of 2023. Since I first flashed, I saw a decent amount of timing corrections across all cylinders (over +/- 3). I started going through a process of elimination to try and see if I can work out what the cause may be.

In August, I went ahead and had the shop I work with replace my plugs and coil packs to see if that made a difference. After replacing, no change in corrections. When I had it in I also added catless DP (not sure if relevant here- but wanted to note).

In terms of fueling I have historically used Shell 93 Octane from three separate stations. For reference, I am located in the US (Ohio specifically). There did not seem to be a difference in impacting the corrections and I've finally moved on from Shell to another brand of 92 from a station called Thorntons. They advertise their 92 as having 10% E- and overall the car seems to drive better on this fuel. They also offer e85 and I am tempted to move to using an e30 blend.

I have attached several logs for reference. My gut still tells me it's the fuel- but hoping for any other opinions or references from anyone else who has run the MHD OTS pump gas maps.

Vehicle
2020 X3M Comp with 28k miles

June 2023
Flashed MHD OTS Stage 1 Map (91 Octane) using Shell 93 Octane fuel
Log 1

Log 2


August 2023
-Replaced plugs (NGK stock gap) and coil packs (Delphi)
-Added Project Gamma Catless DP
-Re-flashed MHD OTS Stage 1 Map to eliminate CEL
-Flashed xHP Stage 2 trans tune (cuz why not)
Log 1

Log 2


November 2023
Switched Fuel to Thorntons 92 Octane
Log 1


As noted at the top, my next step will likely be to move to the OTS E30 map and fuel to see if I observe less corrections. If that doesn't work- custom tune it is. At this point I am hoping those who have used the MHD OTS maps will chime in here with their experience first though. Any other thoughts on my logs are appreciated. I acknowledge I am no expert, but I have searched the forums for all things explaining data logging and am trying to learn more. Thanks!

[Jnat]

Long story short, timing corrections across all cylinders in my humble opinion are different then chasing one or two cylinders. When the corrections appear in all cylinders the map is too aggressive or the gas is not up to snuff for the map and changing gas / adding E / or adding Boostane will calm the corrections down. My opinion, there's no way you have a part problem in every cylinder... good luck but my first base would be to add a gallon or two of ethanol and log the same map and see what happens, it will be better. Some corrections are normal so keep that in mind also (less then 3 deg as long as their working their way to 0 would be somewhat normal depending on circumstance)...

[Mkai082]

Did you try logging with the stock map? I wouldn't be surprised if the stock map on these vehicles shows a lot of timing corrections. There could be a chance of false knock? I know you mentioned changing spark plugs, but maybe try adjusting the gap to whatever MHD recommends for this particular file. If all else fails and you go for a custom tune, tell the tuner to not desensitize your knock sensors, but just to give you a more conservative tune with decent power.

[Brandt51]

What’s the ethanol for? Higher octane?

[Mkai082]

The ethanol should decrease timing pull or knock if the problem is a fuel quality issue.

[Jnat]

Boostane or ethonal will fix this... i''ve used boostane shot on 95 map on several bimmers and it cleans up timing... for whatever reason boostane is not a favorite on these forums but like i said, it works... mostly people report the orange build up that over long periods will make you change your plugs a little more often, 02 sensors a little more often (never had one fail due to this) and people think it clogs cats (maybe but not personally experienced this in almost 8 years of use. ethanol is a great option though also