[335fanatic]

Hey guys,
I'm currently running stage 1 93 bootmod3 and I've notice some knocking especially after I get in and let off the throttle really quickly. I am thinking it could be low quality gas? I always double check I'm filling 93 and I am going to a reputable gas station. I am also running OEM plugs with only 8k on them. Should I flash back to stock and see if it changes? I've attached my logs below any advice would be much appreciated.

https://www.bootmod3.net/log?id=5fd6...0b4331d04f9c61

https://www.bootmod3.net/log?id=5fd6...729b7b35145152

[harkes]

Looks good to me. Try to share a full throttle log. Part throttle is difficult to judge.

[jbiswurm]

Originally Posted by 335fanatic

Hey guys,
I'm currently running stage 1 93 bootmod3 and I've notice some knocking especially after I get in and let off the throttle really quickly. I am thinking it could be low quality gas? I always double check I'm filling 93 and I am going to a reputable gas station. I am also running OEM plugs with only 8k on them. Should I flash back to stock and see if it changes? I've attached my logs below any advice would be much appreciated.

https://www.bootmod3.net/log?id=5fd6...0b4331d04f9c61

https://www.bootmod3.net/log?id=5fd6...729b7b35145152

Patrial throttle knocking is pretty typical. You need to research how to do a proper datalog. Search for a datalog tutorial by thejeremyman. In short, turn off dac, car in 3rd for 6mt, 4th for 8AT, rpms at 2500, start datalog, floor it immediately, keep it floored until 6k rpm minimum, upshift, end datalog.

You cannot tell anything meaningful from normal putting around.

[mike@x-ph.com]

As suggested, do a full log and send it to PTF

[thejeremyman9]

Originally Posted by jbiswurm

Patrial throttle knocking is pretty typical. You need to research how to do a proper datalog. Search for a datalog tutorial by thejeremyman. In short, turn off dac, car in 3rd for 6mt, 4th for 8AT, rpms at 2500, start datalog, floor it immediately, keep it floored until 6k rpm minimum, upshift, end datalog.

You cannot tell anything meaningful from normal putting around.

Datalogging thread: https://f30.bimmerpost.com/forums/sh....php?t=1732327

OP should read, relog, and report back.

[335fanatic]

Thanks for the help guys. I've relogged a few times and the results are below. My timing seems to be worse than it used to be. I tried to crop to the relevant RPMs but I wasn't sure how to so apologize for the little longer than expected end of pull.

https://www.bootmod3.net/log?id=5fd7...0b4331d04f9e79

https://www.bootmod3.net/log?id=5fd7...90c60d7521fe70

[thejeremyman9]

Originally Posted by 335fanatic

Thanks for the help guys. I've relogged a few times and the results are below. My timing seems to be worse than it used to be. I tried to crop to the relevant RPMs but I wasn't sure how to so apologize for the little longer than expected end of pull.

https://www.bootmod3.net/log?id=5fd7...0b4331d04f9e79

https://www.bootmod3.net/log?id=5fd7...90c60d7521fe70

The timing looks fine honestly. You have basically only 1 cyl having a little bit of correction in the 2-3 log.

In the 4th gear log you do have a knock and some timing being pulled but its not nearly as bad as alot of other people trying to run the 93 map to inevitably end up going to the 91 map with 93 gas.

I would also note that your WGDC seems a little bit high for being on stage 1. I would find some other stage 1 logs and compare. You also didnt provide your mod list. OEM DP could explain this.

Also, not sure why but in both logs you slowly lift your foot off of WOT. There's no harm in keeping it WOT throughout the pull.

[335fanatic]

Thanks for the help. I have an aftermarket midpipe and muffler with the OEM dp, and also a vrsf 5" fmic and chargepipe in case that changes anything. I did not mess with the burble on the car either but maybe the OTS map changed it.

[thejeremyman9]

Originally Posted by 335fanatic

Thanks for the help. I have an aftermarket midpipe and muffler with the OEM dp, and also a vrsf 5" fmic and chargepipe in case that changes anything. I did not mess with the burble on the car either but maybe the OTS map changed it.

IC is helping your IATs, but they are very low, so not a factor in timing really (except helping it).

Catback exhaust is basically irrelevant for the logs (wont affect timing, WGDC, etc), especially with OEM DP. OEM DP could explain slightly higher WGDC than what i recall seeing.

Burble also not a factor in this discussion as that is just for sound.

Overall log looks fine though. Maybe log again on next tank and see if you still get a knock.

[335fanatic]

Thank you for your help. I've heard good and bad reviews about the Wawa gas I'm using so I'll switch to exxon or Conoco and see if that helps

[jbiswurm]

Originally Posted by 335fanatic

Thank you for your help. I've heard good and bad reviews about the Wawa gas I'm using so I'll switch to exxon or Conoco and see if that helps

I run the stage 91 ACN map even with "93" gas. Was getting timing kind of like yours even on the 91 map.

IMHO folks chase all sorts of esoteric variables, when in reality 75%+ of your results will be simply tied to gas quality.

I would recommend flashing 91 to see if your timing and knock clean up a little

[335fanatic]

So I ended up getting a new tank of gas yesterday, and the knock seemed to be drastically reduced. This isn't the case apparently because at half tank it came back just as bad for some reason. I get no knock on wot only casual cruising around. I'm starting to think I might have a vacuum leak or another mechanical issue rather than a tune issue as I flashed back to stock and the issue still persists.

[tpoddar]

Part throttle knocking shouldn't be a concern since the engine is actively working to optimize for fuel efficiency. As long as WOT logs are clean, you should be fine.

[thejeremyman9]

Originally Posted by tpoddar

Part throttle knocking shouldn't be a concern since the engine is actively working to optimize for fuel efficiency. As long as WOT logs are clean, you should be fine.

Exactly this. Knock during light throttle/cruise is totally normal, and somewhat expected because the of the way the engine is working as noted above. The AFRs and timing are on the edge of knock to minimize emissions and maximize fuel economy.

[BimmerWu]

Originally Posted by tpoddar

Part throttle knocking shouldn't be a concern since the engine is actively working to optimize for fuel efficiency. As long as WOT logs are clean, you should be fine.

It annoyings me now. BM3 Stage1 MultiMap ACN91 + Ron98 (China SINOPEC)

engine knock in low rpm. WOT is fine

https://www.bootmod3.net/log?id=6756...63e0304c9ba587