[Lulz_M3]

Please list your vehicle specific information and what ROM you have. Most importantly, whether you have had your HPFP replaced and/or DME Software updated from BMW, 29.2+newer.

Thanks for all who are willing to participate.

[Lulz_M3]

2007 BMW 335i 6MT, I8AOS ROM Original HPFP and software never updated. Boost oscillations only since flashing to S2+FMIC.

[nitehawk]

2007 BMW 335i 6MT, I8AOS ROM, HPFP replaced from recall, most recent software update
Minor boost oscillations on S2+FMIC Aggressive, v401. It was much more evident on v3.0

[vasillalov]

2008 BMW 335i 6MT, I8A0S. Third HPFP (replaced on recall). Running latest BMW software. Boost oscillations present on all maps but mostly noticeable on S2+FMIC Aggressive v.3.01

It is definitely firmware/map related because the boost oscillations are much improved on 4.01 beta maps (but not gone), but then I get overboost error codes all the time.

EDIT:

Here are two logs, one from 3.01 and another from 4.01 beta. Same car, same mods, same fuel, same road, similar weather conditions. Follow the boost lines and notice how much choppier is 3.01 compared to 4.01:

3.01:


4.01b:

[raceyBMW]

Can you explain what you feel or what is an example of boost oscillations (graphs, etc.?)

[AU335i]

2008 BMW 335i 6MT, I8AOS ROM, HPFP replaced and Software Updated during recall
Boost Oscillations with Stg.2+FMIC on v.301 and v.4xx

[nitehawk]

Some logs attached as a reference

[vasillalov]

Originally Posted by raceyBMW

Can you explain what you feel or what is an example of boost oscillations (graphs, etc.?)

The "butt dyno" sees drops of power during oscillations while accelerating in part throttle. Also, this can be heard via the exhaust note in the car.

Now, this happens mostly during part throttle acceleration on 4th, 5th gears. If I go WOT from 1st and I row through all of them, it is almost impossible to get an oscillation.

[BMWsky]

2008 6MT IJEOS, latest software...latest HPFP.

Oscillations were more pronounced on 3.01 stage 2+, but ran smoother than 4.01 stage 2+.

[mikead_99]

2008 6MT 135i, IJEOS. HPFP, injectors, and code update this spring under recall.

Definite oscillations under heavy load low to mid rpms in 3rd gear WOT pulls with 4.01 2+, no issues with stg 2. Never tried 3.01 to know if it was any worse, but pretty bad with 4.01.

[gmazzu]

How does one know what BMW code they are running? Can the Cobb tell you that?

[onesuperboi]

Welcome back Vas!

[dfv2]

08 yes to the HPFP no to the software reflash, IJE0S, fixed 80% of my issues by tuning the various WGDC PID tables (mostly them less aggressive).

[gboop]

2007 6MT I8AOS - New HPFP done under recall, flashed to latest software last year.

Getting minor part throttle drivability issues described by others plus load target overshoots on all maps. Don't have such issues when using Procede 2.5.

Hoping COBB will be able to fully eliminate these problems with OTS maps. Otherwise would we need multiple wastegate profile maps like they do for Subies?:

From COBB STI map download page

• Normal Wastegate
• Low Wastegate - For vehicles exceeding target boost
• High Wastegate - For vehicles not reaching target boost

[Zasquatch]

2007 335i 6MT, I8AOS, HPFP replaced, injectors replaced, coils replaced... It is absolutely a map issue, and COBB has said the next maps released will fix the issue (supposedly very soon). I've been running an alpha test map from awhile ago from Rob and it completely fixes all issues on my car.... and my car oscillated BAD on the S2+ maps.

[AU335i]

Originally Posted by Zasquatch

2007 335i 6MT, I8AOS, HPFP replaced, injectors replaced, coils replaced... It is absolutely a map issue, and COBB has said the next maps released will fix the issue (supposedly very soon). I've been running an alpha test map from awhile ago from Rob and it completely fixes all issues on my car.... and my car oscillated BAD on the S2+ maps.

was there any kind of difference in performance? datalogs of alpha maps?

[Alpina_B3_Lux]

IJEOS ROM, HPFP replaced two years ago, several software updates (due to the need to overwrite other tunes), running stage 3 v.401 with RB turbos

Boost oscillations, part throttle driveability problems, car continues to accelerate when going off throttle, severe lag when going on throttle after part throttle.

JB4 G5 / PROcede testing coming soon.

Alpina_B3_Lux

[ironman1982]

IJEOS, on 3rd HPFP (2nd was installed at ~12k miles because 1st failed, 3rd installed due to recall but 2nd had no issues), 2 injectors replaced under recall at same time as 3rd HPFP install. New plugs at 40k....have ~45k or so on car now. Latest BMW software. I have part throttle oscillations when just cruising around 2000-2500 RPM as well as beginning to accelerate from part throttle to more aggressive throttle (not WOT). It is better with each iteration of maps. I am on Stg 1+ FMIC 4.01 right now. I have Forge DV, Helix FMIC, AFE dual cone intake, Autobahn Exotics CBE.

[Zasquatch]

Originally Posted by AU335i

was there any kind of difference in performance? datalogs of alpha maps?

Yeah, the car was basically unable to go WOT it would oscillate so bad.

Here's a log with the oscillations:



Here's one after the fix:

[Lulz_M3]

I was hoping we would see a smoking gun emerge but it appears to be totally dependant on mechanical wastegate variances. Like Zasquatch said they already have a beta map for the wg fix, ive been testing it for about a month and it cured my issues.

[bryce]

not to come off as a 'fanboy' or 'anti-cobb,' but until cobb gains better control of boost (i.e. direct control over wastegates through an external boost controller), i think they're going to be the 2nd best tune on this platform. i'd love for them to release an external meth control/boost control box, that would be the best of both worlds (piggy back versus flash)

[rader1]

Originally Posted by bryce

not to come off as a 'fanboy' or 'anti-cobb,' but until cobb gains better control of boost (i.e. direct control over wastegates through an external boost controller), i think they're going to be the 2nd best tune on this platform. i'd love for them to release an external meth control/boost control box, that would be the best of both worlds (piggy back versus flash)

For most people running Cobb there are no boost control issues. I've only rarely experienced oscillations and that is when I try to really push the car in a gear or two higher than I should've been. The torque really spoils us in these cars and it's easy to forgot how to drive properly sometimes.

I prefer load based boost control as opposed boost targeting. Sure boost targeting is easier(and the only option for piggies) but load based provides more consistency. Getting the boost control system figured out is going to take some time but the rewards will be worth it based on what I've seen.


With ATR(and non beta 4xx maps released) the WG stiffness variance will become less and less of an issue.