Hiestitation under throttle - N54Tech.com

mixhali · 2019-01-25 15_36_32 Map-6.zip (106.7 KB, 64 views)

Hi guys, I have been trying to get to the bottom of an issue with my 335 for a while now, it seems to be getting worse which is why i make this post. The issue is that every once in a while when i throttle, the car looses power for a split second. it can be quiet abrupt. it then powers and resumes. this can be from take off or even when just coasting and re-applying throttle. I have recently changed the Vanos solenoids as in my mind i drew a possible link. However no improvement, but my cold starts have improved so not a total loss. I noticed in my JB4 logs however that my throttle position does not appear to be very smooth. And i have observed that it behaves like this when the incident occurs. So maybe bad throttle data is causing the ECU to go a bit nuts
. Even under very light pedal throttle, the throttle position is reporting 100%. Could the throttle body sensor be the culprit here that is causing this hesitation?

Terry @ BMS · 02-02-2019, 10:01 AM

It's older JB4 firmware so I'd update that to start.

Boost is on target and throttle is moving as expected. I think I might try lowering menu11 to 0 to see if that has any effect, less boost at partial throttle.

mixhali · **More feedback -** 02-02-2019, 09:37 PM

Thanks for the quick response terry, Another rpoint i should have added, I have run the car for a period of time on map 4 and the issue was still present. Ill try the upgrade and setting change you suggested and go for a run and report back logs

On a side note, feature suggestion for the mobile app. It would be great if rather than having to go in and turn on logs and save a log that if the app was actually automatically capturing last minute of log data and if i push a capture log button it auto saves that one minute to a file. Reason for this suggestion is that when the car is behaving at its worst, I've never got the logging going!

Cheers

E90 M335i · 02-03-2019, 12:04 AM

The Jb4 app has an auto data logging option when you're at 50%+ throttle.

mixhali · 02-03-2019, 05:45 AM

Quote:

Originally Posted by E90 M335i

The Jb4 app has an auto data logging option when you're at 50%+ throttle.

Sometimes you need logs for under 50% throttle. I got this idea while watching the F1, The cars have a button on the steering wheel to log a incident in the logs for review later.

mixhali · 02-03-2019, 05:51 AM

Terry, I did the upgrade and changed the settings as advised. Good news is that during the drive I did it didn't hesitate once, however I thought I would do a few pulls and now the car wont hold the map. It is reverting straight back to map 4 and I think is reporting overboost. No codes are thrown.

Dave @ BMS/Fuel-It! · 02-03-2019, 10:50 AM

Quote:

Originally Posted by mixhali

Terry, I did the upgrade and changed the settings as advised. Good news is that during the drive I did it didn't hesitate once, however I thought I would do a few pulls and now the car wont hold the map. It is reverting straight back to map 4 and I think is reporting overboost. No codes are thrown.

Can you just upload the CSV file. Thanks

mixhali · 02-03-2019, 07:44 PM

Quote:

Originally Posted by Dave @ BMS/Fuel-It!

Can you just upload the CSV file. Thanks

Done

Dave @ BMS/Fuel-It! · 02-04-2019, 08:34 AM

Quote:

Originally Posted by mixhali

Done

Your current setup is almost exactly what I had on my first 335, about 4 years ago!

You are definitely overboosting... in your duty bias settings- from 3k to redline lower that by 10 for now.

And can I see a log in map 1 or 2?

Also note- your FF is at 147 & 150 in the Logs- you might have a leak somewhere.

You disabled FF Gain / followed Terry’s hybrid FUD setting protocol correct?

mixhali · 02-04-2019, 09:37 PM

Quote:

Originally Posted by Dave @ BMS/Fuel-It!

Your current setup is almost exactly what I had on my first 335, about 4 years ago!

You are definitely overboosting... in your duty bias settings- from 3k to redline lower that by 10 for now.

And can I see a log in map 1 or 2?

Also note- your FF is at 147 & 150 in the Logs- you might have a leak somewhere.

You disabled FF Gain / followed Terry’s hybrid FUD setting protocol correct?

Hey Dave, interesting about the boost leak. i have struggled with some of the hoses over the years as they just arn't perfect in terms of length for my setup. Might be time check. I looked at the logs and i see the FF in the thousands. im not sure where you get the 147/150 from.

The orginal setup was done by a guy in Australia. He sold me all the parts and i shipped them to Malaysia and fitted them. I sent him logs and he sent back tunig changes. To be fair it hasn't been tuned in a long time. I also now usually run RON 100 as it has become available recently. however these pulls have been done with pump 97 as I was desperate to fill and was not close to a gas station that stocked 100

The new firmware and the changes that terry suggested seemed to have smoothed out the power. The power came on quiet aggressively previously.

After changing the bias it now holds the map and hasn't skipped back to map 4 since.

You said you had the same setup, did you have DCT transmission? Will have some follow on questions if so.

I did three pulls, maps 1,2,6 again. After the map 6 my serpentine belt snapped. Not sure how that happened as it was recently changed. Maybe a pulley caused it. Am going to recover it now.

Dave thanks for all your Support.

Dave @ BMS/Fuel-It! · 02-04-2019, 09:57 PM

Quote:

Originally Posted by mixhali

Hey Dave, interesting about the boost leak. i have struggled with some of the hoses over the years as they just arn't perfect in terms of length for my setup. Might be time check. I looked at the logs and i see the FF in the thousands. im not sure where you get the 147/150 from.

The orginal setup was done by a guy in Australia. He sold me all the parts and i shipped them to Malaysia and fitted them. I sent him logs and he sent back tunig changes. To be fair it hasn't been tuned in a long time. I also now usually run RON 100 as it has become available recently. however these pulls have been done with pump 97 as I was desperate to fill and was not close to a gas station that stocked 100

The new firmware and the changes that terry suggested seemed to have smoothed out the power. The power came on quiet aggressively previously.

After changing the bias it now holds the map and hasn't skipped back to map 4 since.

You said you had the same setup, did you have DCT transmission? Will have some follow on questions if so.

I did three pulls, maps 1,2,6 again. After the map 6 my serpentine belt snapped. Not sure how that happened as it was recently changed. Maybe a pulley caused it. Am going to recover it now.

Dave thanks for all your Support.

Thanks for the kind words

I got the FF being 147-150 based on the prior logs. Top column 8 over from the left.

Get your belt fixed, make sure nothings bent- and we can start dialing in your setup.

Feel free to shoot me a Pm & we can chat about your setup a bit more in depth. Glad you aren’t being thrown to map 4 anymore