Inconsistent pulls and loss of power? Stage 2 BM3 Tune.

[M3hf80]

Hey guys,

I've been running BM3 stage 2 tune for about 4-5 months now and recently I started to notice an issue while going WOT in 2nd gear. My car is a 6 speed and my mods are RK Intakes, VRSF DP, MPE.

I typically WOT in 2nd while the car is warmed up, and for those of you running the OTS map you know how it feels in 2nd. I started experiencing power loss going wot in 2nd gear, one pull from 3k-7k rpm would be crazy and then the next pull (another 2nd gear pull) would feel super linear like if I was in 6th gear. No codes or anything, it's just happening more and more frequent and I'm not sure what it is.

Other than 2nd gear, every other gear feels fine. Can someone chime in? I would try to log it but it happens so randomly I'm not sure when I can catch it. Someone local said it can be the gas since I'm running regular stage 2 BM3 while living in CA but others seem to have no issues?

Please chime in. Thanks!

[TopJimmy]

Did you reset adaptations and re-flash? I had that happen once on an OTS map, thought I shifted to 4 instead of 2. Couldn't reproduce it, but I flash a lot playing with tunes and fuels.

[M3hf80]

Originally Posted by TopJimmy

Did you reset adaptations and re-flash? I had that happen once on an OTS map, thought I shifted to 4 instead of 2. Couldn't reproduce it, but I flash a lot playing with tunes and fuels.

I did reset adaptation and re flash because the car would not rev match when it should have that's why I cleared adaptations but it had nothing to do with consistency when it comes to pulls.

[TopJimmy]

You're gonna need a log of it. Can you get us a two good captures of 1st through 4th gears so we can review and compare? Post the log links.

[tanzm4_]

If you're getting no major CEL it's probably gas. Try filling 3 gal of e85 and the rest 91 and see if that solves anything. Usually the gas here in CA is pretty garbage and when you put the car to push stage 2 numbers the fuel lacks.

[landonvan]

The other thing to think about is doing back to back pulls will result in power loss. Your IAT clime and the car pulls timing. I have not seen the bmw tables. But I tune gm cars and anything over 115 and the ecm starts to pull timing.

[M3hf80]

this was never a problem on stage 1 so why now all of a sudden I need different fuel content?

[M3hf80]

Originally Posted by landonvan

The other thing to think about is doing back to back pulls will result in power loss. Your IAT clime and the car pulls timing. I have not seen the bmw tables. But I tune gm cars and anything over 115 and the ecm starts to pull timing.

I'm not talking about directly back to back pulls, my first pull of the day can be super sluggish and then the next one will make me feel like I can take on a GTR.

[TopJimmy]

Gotta log it, or we're guessing.

[n8dgr84]

I'd put money on winter gas.
Not sure about your quality of gas but here I have to mix in 15% ethanol to run properly.

[Electric]

Might be stupid but is your traction control on (not in MDM) and you could be spinning and it cutting power. If the car feels good in 3rd each time that could be the issue.

When I first got my car tuned (BM3 stage 2), the car felt kinda slow in 2nd bc of the spinning.

[Kilabyte]

Is your top mount stock? Check the coolant level. That was my issue.

[M3hf80]

Originally Posted by n8dgr84

I'd put money on winter gas.
Not sure about your quality of gas but here I have to mix in 15% ethanol to run properly.

Originally Posted by n8dgr84

I'd put money on winter gas.
Not sure about your quality of gas but here I have to mix in 15% ethanol to run properly.

I was going to try this but I've never ran E85 before so I was kind of scared to randomly put E85 out of frustration n confusion lol

[M3hf80]

Originally Posted by Electric

Might be stupid but is your traction control on (not in MDM) and you could be spinning and it cutting power. If the car feels good in 3rd each time that could be the issue.

When I first got my car tuned (BM3 stage 2), the car felt kinda slow in 2nd bc of the spinning.

Originally Posted by Electric

Might be stupid but is your traction control on (not in MDM) and you could be spinning and it cutting power. If the car feels good in 3rd each time that could be the issue.

When I first got my car tuned (BM3 stage 2), the car felt kinda slow in 2nd bc of the spinning.

You're onto something here, I do have traction control on 100% of the time as I foolishly flashed my MDM to GTS MDM and now that's too much slip for me so I always keep it on lol.

The traction light comes on during the pulls but I'm doing it on the same road back n forth so I was expecting the pulls to be consistent all across. I was always hesitant on pointing fingers as the gas because my car felt fine on stage 1. I did not know the car cuts power like that.

[E92TiAg335i]

I'll bet 100 bucks on bad gas. If you click on my name, you'll see a few threads that i recently created.

I created some logs and sent to PTF. They noticed my ignition was all over the place— turned out to crap winter gas.

Got good gas at costco (yes, it's considered "top tier") and problem went away. car spun 3 gears on the way out. I couldn't stop smiling ear to ear since i figured out the problem.

[horsepower_and_hounds]

What he said.......

A couple of things.

How in the hell can you do a 2nd gear pull on stg 2 93 without TC on? I bet it is pulling timing due to TC intervening. When I ran stg 2 93 and did a dig it spun till 3rd gear

When you re-flash or clear adaptations you should give it a coupe days to adapt up to full potential. it is a self learning DME and you should do a few pulls over a couple days for it to learn up to the tune.

Last when you did pulls different times of day what were the outside elements like.... temps make a big difference sometimes.

Always log when something feels off.... it will tell you wonders. Gas can be the route to most of our evils.....

Just some tips from a old guy

[mike@x-ph.com]

Originally Posted by TopJimmy

Gotta log it, or we're guessing.

+1

[TopJimmy]

TC/MDM will take your power, or eat brakes, or freak you out. It's not consistent either. I prefer to drive in full manual no-nanny mode and learn how the car behaves.

To figure out a problem we need a log of 4th gear, WOT from 2500-7100RPM. That's about 40-130 Mexican MPH. Mode should be Sport+ with DCT fully disabled (hold MDM button until DCT Off lights). If something goes or sounds weird just back off. Single gear rip shows a ton of clean data.

Post a log link.

[M3hf80]

Originally Posted by TopJimmy

TC/MDM will take your power, or eat brakes, or freak you out. It's not consistent either. I prefer to drive in full manual no-nanny mode and learn how the car behaves.

To figure out a problem we need a log of 4th gear, WOT from 2500-7100RPM. That's about 40-130 Mexican MPH. Mode should be Sport+ with DCT fully disabled (hold MDM button until DCT Off lights). If something goes or sounds weird just back off. Single gear rip shows a ton of clean data.

Post a log link.

https://www.bootmod3.net/log?id=5ff5...729b38c9d2c707

https://www.bootmod3.net/log?id=5ff5...0b4328aadd5791

Logs are up! Please help. Shout out to TanzM4 for helping me log this shit!

[M3hf80]

Originally Posted by horsepower_and_hounds

What he said.......

A couple of things.

How in the hell can you do a 2nd gear pull on stg 2 93 without TC on? I bet it is pulling timing due to TC intervening. When I ran stg 2 93 and did a dig it spun till 3rd gear

When you re-flash or clear adaptations you should give it a coupe days to adapt up to full potential. it is a self learning DME and you should do a few pulls over a couple days for it to learn up to the tune.

Last when you did pulls different times of day what were the outside elements like.... temps make a big difference sometimes.

Always log when something feels off.... it will tell you wonders. Gas can be the route to most of our evils.....

Just some tips from a old guy

https://www.bootmod3.net/log?id=5ff5...729b38c9d2c707

https://www.bootmod3.net/log?id=5ff5...0b4328aadd5791

[TopJimmy]

Originally Posted by M3hf80

https://www.bootmod3.net/log?id=5ff5...729b38c9d2c707

https://www.bootmod3.net/log?id=5ff5...0b4328aadd5791

Logs are up! Please help. Shout out to TanzM4 for helping me log this shit!

I took your first log ...707 and isolated just the Ignition Timing 1-6 and the Knock (click on everything else in the bottom list to remove from graph). In both the 3rd gear and also the 4th gear part your cylinder 4 timing falls apart first and then other cylinders join. When the timing is pulled your 3rd gear boost peak also dips, which you may have felt as lost power. and then there was that single knock at 5611RPM.

The second log ...791 is also similar in the timing breaking up and one knock, but cylinder 2 leads the breakup and other cylinders join in your 3rd gear part, then cylinders 4 and 6 lead the breakup in the 4th gear part.

I'm thinking you have crappy gas and need to drive it all out first, then fill up with 93 at a known quality spot. Don't add ethanol, just get this possible junk tank run out. Don't push hard either, because of the knocks. I'm thinking bad gas because the timing issue affects a variety of cylinders, not 4 alone. Drive in the new gas for 10 miles and then log again same way.

If you still have problems then I would examine the plug in cylinder 4 against the others. You may have a crack in the ceramic. If you do get into this job just put in new OEMs or NGKs at 0.021" and be done with questioning plugs. If you still get problems after new plugs mark your coil #s and swap them around to the other cylinder bank and see if the problem follows one (move Coil#1-2-3 into 4-5-6, and 4-5-6 into 1-2-3, if Cyl#1 acts up instead of Cyl#4 then the problem is likely Coil#4).

I hope the gas is the quick fix!

[Kilabyte]

^ If it's really a gas problem and you're filling up at random little gas stations and not Shell then there's your issue.