Data log review

[Jonb70]

Hey all,
I’ve been struggling with a rough idle issue and was wondering if anyone could find anything in my data logs. Car has fresh fcp euro ngk 97506 plugs gapped at .022 torqued to spec and oe Delphi coils. Clean maf sensors as well. My next guess is my bms elite intake. It is fbo with stock top mount at 55k miles. I’ve been stage 2 since 50k and after reaching out to ptf support they suggested flashing a lower octane tune. The car runs great when warmed up and throws no codes.

Stage 2 93 on 3/3/24
https://bootmod3.net/log?id=65e524ce58ba630e703eddc2

Stage 1 91 3/10/24
https://bootmod3.net/log?id=65edefbb31d60016dec05d8b

I also have cold start logs but not sure if they’re useful.

[sly1types]

Looks like you have decent boost deviation on the first log. I would check your charge pipes. That might also cause your idle issue.

[Jonb70]

Originally Posted by sly1types

Looks like you have decent boost deviation on the first log. I would check your charge pipes. That might also cause your idle issue.

I think you just determined my issue. I bought my vrsf chargepipes used and didn’t put much thought into installing. Looking back at photos it looks like they didn’t come with the o-ring installed and I don’t remember reusing my oem ones. Would the boost deviation cause the timing corrections as well?

[MineralWhiteF80]

Originally Posted by Jonb70

Would the boost deviation cause the timing corrections as well?

The post-MAF air leaks due to the missing O-rings are what is causing both boost deviation and air/fuel mixture problems that result in timing corrections.

edit: also, your open cone filter intakes can cause a rough cold start idle problem in some situations. This is quite a common issue, especially if the small air hose O-ring connected to the driver-side intake isn't sealing correctly or if the MAFs don't perfectly seat onto the intake pipe mating surfaces. I have a BMS intake, and the CNC mounting plates for the MAFs weren't drilled correctly, which caused the sensor to want to go in at an angle and not seal well. I had to modify the MAF mounting holes to make it seat right. These reasons (and more) are why most people get rid of aftermarket intakes and return to the OEM intakes that improve drivability.

[Jonb70]

Originally Posted by MineralWhiteF80

The post-MAF air leaks due to the missing O-rings are what is causing both boost deviation and air/fuel mixture problems that result in timing corrections.

edit: also, your open cone filter intakes can cause a rough cold start idle problem in some situations. This is quite a common issue, especially if the small air hose O-ring connected to the driver-side intake isn't sealing correctly or if the MAFs don't perfectly seat onto the intake pipe mating surfaces. I have a BMS intake, and the CNC mounting plates for the MAFs weren't drilled correctly, which caused the sensor to want to go in at an angle and not seal well. I had to modify the MAF mounting holes to make it seat right. These reasons (and more) are why most people get rid of aftermarket intakes and return to the OEM intakes that improve drivability.

Well you guys hit the nail on the head. My chargepipes have no o-rings! Throwing them on now as well as putting stock intake back on with fresh oem filters. Then will reset adaption using bm3 and I’m hoping I can finally put this issue to rest. Thank you for the help!

[Jonb70]

Originally Posted by MineralWhiteF80

The post-MAF air leaks due to the missing O-rings are what is causing both boost deviation and air/fuel mixture problems that result in timing corrections.

edit: also, your open cone filter intakes can cause a rough cold start idle problem in some situations. This is quite a common issue, especially if the small air hose O-ring connected to the driver-side intake isn't sealing correctly or if the MAFs don't perfectly seat onto the intake pipe mating surfaces. I have a BMS intake, and the CNC mounting plates for the MAFs weren't drilled correctly, which caused the sensor to want to go in at an angle and not seal well. I had to modify the MAF mounting holes to make it seat right. These reasons (and more) are why most people get rid of aftermarket intakes and return to the OEM intakes that improve drivability.

Originally Posted by sly1types

Looks like you have decent boost deviation on the first log. I would check your charge pipes. That might also cause your idle issue.

Well now I’m confused again. Added the o-rings and returned to stock intake. I meticulously reassembled the car making sure everything was snug and tight. This morning on my way to work I did some data logging and it seems my timing corrections may have gotten worse. I’m stumped at this point.

Attaching log links.

https://bootmod3.net/log?id=65fac603ab4af232b5d07866

https://bootmod3.net/log?id=65fac32a173e641b53847d6e

https://bootmod3.net/log?id=65fac3d909e0ec5aad0f8f0a

[MineralWhiteF80]

Originally Posted by Jonb70

Well now I’m confused again. Added the o-rings and returned to stock intake. I meticulously reassembled the car making sure everything was snug and tight. This morning on my way to work I did some data logging and it seems my timing corrections may have gotten worse. I’m stumped at this point.

Does the car seem to run OK now, and the only thing giving you pause is the data log information? I think we need to be sure everyone (including me) is accurately interpreting the log file information and not thinking there is a problem when there isn't. In a perfect world, you would think that the timing values for all cylinders should always be identical and run exactly at the target ignition timing. But the world is far from perfect, and I know these engines can do odd things so they can meet their load (power) targets.

It can still be an issue with your fuel quality. If this were my car, I'd put 2 gallons of E85 in it, and after 5-10 minutes of ensuring that the fuel is properly mixed in the tank, I'd do some more logs and see if your timing values are most consistent with each other.

The second option is to flash back to the stock tune to see what happens.

Flashing to stock tune or adding 2 gals of E85 are easy things to try. If those dont do anything different, you can start looking at other possibilities.

[Jonb70]

Originally Posted by MineralWhiteF80

Does the car seem to run OK now, and the only thing giving you pause is the data log information? I think we need to be sure everyone (including me) is accurately interpreting the log file information and not thinking there is a problem when there isn't. In a perfect world, you would think that the timing values for all cylinders should always be identical and run exactly at the target ignition timing. But the world is far from perfect, and I know these engines can do odd things so they can meet their load (power) targets.

It can still be an issue with your fuel quality. If this were my car, I'd put 2 gallons of E85 in it, and after 5-10 minutes of ensuring that the fuel is properly mixed in the tank, I'd do some more logs and see if your timing values are most consistent with each other.

The second option is to flash back to the stock tune to see what happens.

Flashing to stock tune or adding 2 gals of E85 are easy things to try. If those dont do anything different, you can start looking at other possibilities.

The car seemed to run great and pull harder than it has before which is why the logs confused me so much. So maybe it is somewhat normal for the motor? I’ll flash to stock and do some data logging tomorrow depending on weather. Unfortunately e-85 isn’t readily available in ct but fcp euro is. Do they carry anything I can put in the tank to help? I used injector cleaner about 2k miles ago. Thank you for the help.

[Jonb70]

Gas has been shell 93 the last 3 fill ups from a pretty busy station

[MineralWhiteF80]

Originally Posted by Jonb70

So maybe it is somewhat normal for the motor? I’ll flash to stock and do some data logging tomorrow depending on weather.

Just to give you some comparison- here are logs from my car with various tunes. My Stage 1 93 octane and Stage 2 93 octane look very similar to yours as far as timing values getting pulled, so it's possible that this is how these tunes work. Or, both of our cars are screwed up. My car accelerates strong without any hesitation.

Stage 1, 93 Octane- 3rd and 4th gear:
https://www.bootmod3.net/log?id=6271...729b4c60f22473

Stage 1, 93 Octane - 5th gear:
https://www.bootmod3.net/log?id=6271...729b4c60f22470

Stage 2, 93 Octane - 3rd gear:
https://www.bootmod3.net/log?id=6366...729b33adc07366

Multimap Stage 2, 41% Ethanol - Reduced max boost to 10psi= PERFECT TIMING
https://www.bootmod3.net/log?id=6398...0b4374e1ea23dd

Originally Posted by Jonb70

Unfortunately e-85 isn’t readily available in ct but fcp euro is. Do they carry anything I can put in the tank to help? I used injector cleaner about 2k miles ago. Thank you for the help.

The other [more expensive] option is finding a gas station or race track that sells 100 octane or higher. All you are looking for is more octane to fight timing pull. I'm not a fan of any "octane booster" or other snake oil people sell so I wouldn't bother.

[Jonb70]

Originally Posted by MineralWhiteF80

The other [more expensive] option is finding a gas station or race track that sells 100 octane or higher. All you are looking for is more octane to fight timing pull. I'm not a fan of any "octane booster" or other snake oil people sell so I wouldn't bother.

So looking at your logs it seems there are similar timing corrections. I’m going to assume it’s normal bmw bs and go about my business. Thank you so much for the help. This community is great!