[Zach1328]

I ordered the JB4 USB cable a few days ago and installed it last night so I can finally do some logging! I'm just trying to iron out some issues before I upgrade to the Walbro 255 so I can start running ~70% E85.

I'm new to this logging stuff so any help analyzing this log is greatly appreciated!
Mods: JB4 Map 5 & DCI's (93 oct. pump)


I've been having some issues with terrible turbo lag - its way under-boosting for a few seconds, but is right on target once the turbos finally spool up.
Could this possibly be the pressure converter? Waste-gate issues?

Ignition timing also looks really high especially at the beginning of the pull. What could this be? I know I need new ignition coils soon, but would it cause ignition to be that bad?

FWIW: My LPFP was sitting around 65 even with 100% 93 octane which seems pretty low considering I didn't even have any E85 in the tank.

[e92_enthusiast_1]

upload it to datazap and you'll get a greater response. Easier to read.

http://datazap.me

Example: Datazap Example

[Zach1328]

Originally Posted by e92_enthusiast_1

upload it to datazap and you'll get a greater response. Easier to read.

http://datazap.me

Example: Datazap Example

I can't seem to upload any logs on that website. When I click save it takes me to a blank page: http://datazap.me/upload
I think I need to get some more logs so I can export them with the proper extension.

Here's another log in the meantime. 4th Gear, JB4 G5 & DCI's with 93 octane pump gas. Temperature was around 96F and very humid.


Any ideas on that terrible lag? It doesn't feel very fast anymore because the boost builds so slowly I want that initial jerk back into the seat again

[e92_enthusiast_1]

You're sure you're not just use to it now? I had the same thoughts as you. Wanted the jerkiness back. So i went more aggressive. lol welcome to the power bug.

Originally Posted by Zach1328

I can't seem to upload any logs on that website. When I click save it takes me to a blank page: http://datazap.me/upload
I think I need to get some more logs so I can export them with the proper extension.

Here's another log in the meantime. 4th Gear, JB4 G5 & DCI's with 93 octane pump gas. Temperature was around 96F and very humid.
Attachment 1076547

Any ideas on that terrible lag? It doesn't feel very fast anymore because the boost builds so slowly I want that initial jerk back into the seat again

[Zach1328]

Originally Posted by e92_enthusiast_1

You're sure you're not just use to it now? I had the same thoughts as you. Wanted the jerkiness back. So i went more aggressive. lol welcome to the power bug.

Lol I think it is the power bug! My 535i feels hopeless when I go WOT yet most people think even my stock 535i is pretty quick. My friends 04 cobra used to feel blistering fast, but now when I ride in it I think "Meh, needs more power!"

However, my 335i is definitely under-boosting quite a bit for the first 2-3 seconds while those damn turbos take their time to spool.
I don't think it could be a boost leak because wouldn't the boost never reach the max target? It's pretty much perfectly on target after that initial lag.

[DuDai]

Quick question, what are your wastegate settings at? Menu 10&12? Adjusting those a certain way can attribute to a lot of lag. I know my car has lag initially but it's due to my settings.

[sirdaft1]

Originally Posted by Zach1328

Lol I think it is the power bug! My 535i feels hopeless when I go WOT yet most people think even my stock 535i is pretty quick. My friends 04 cobra used to feel blistering fast, but now when I ride in it I think "Meh, needs more power!"

However, my 335i is definitely under-boosting quite a bit for the first 2-3 seconds while those damn turbos take their time to spool.
I don't think it could be a boost leak because wouldn't the boost never reach the max target? It's pretty much perfectly on target after that initial lag.

Any half engine lights? And have your boost solenoids/pressure converters (same thing) ever been replaced? I just replaced mine after suffering from lazy boost (under target). Odd thing is that you're on target higher in the rpms. Is it consistently hitting full boost higher in the revs?

[Zach1328]

Originally Posted by sirdaft1

Any half engine lights? And have your boost solenoids/pressure converters (same thing) ever been replaced? I just replaced mine after suffering from lazy boost (under target). Odd thing is that you're on target higher in the rpms. Is it consistently hitting full boost higher in the revs?

I've been getting engine lights occasionally at WOT with no codes or effects. The engine light just pops up for 15-30 seconds then disappears - no limp mode or anything like that.

Yes I have the boost target set up on my oil gauge a lot and its always right on target higher in the revs. It's only that initial 2-3 seconds after going WOT I can hear the turbos taking forever to spool, but once they get going its perfectly on target.

I bought the car about 3 months ago with minimal records so I'm not sure if the boost solenoids have been changed. I doubt it though because there is nothing to indicate they have been replaced.

Boost solenoids are definitely on my list of things to replace soon. Is there anything else that could cause this kind of under-boost/turbo lag so I can order it all at the same time?

[j1gilles]

Originally Posted by Zach1328

I've been getting engine lights occasionally at WOT with no codes or effects. The engine light just pops up for 15-30 seconds then disappears - no limp mode or anything like that.

Yes I have the boost target set up on my oil gauge a lot and its always right on target higher in the revs. It's only that initial 2-3 seconds after going WOT I can hear the turbos taking forever to spool, but once they get going its perfectly on target.

I bought the car about 3 months ago with minimal records so I'm not sure if the boost solenoids have been changed. I doubt it though because there is nothing to indicate they have been replaced.

Boost solenoids are definitely on my list of things to replace soon. Is there anything else that could cause this kind of under-boost/turbo lag so I can order it all at the same time?

Vacuum leaks and wastegate issues...

[Zach1328]

Originally Posted by j1gilles

Vacuum leaks and wastegate issues...

Ok thank you. I'll do a smoke test for vacuum leaks when I get a chance. Wouldn't a vacuum leak cause Max Boost to be below target as well though?

Definitely having waste-gate issues. I'm driving it up to Colorado on Sunday which will put me at 80k miles so I need to get to a dealership soon to see if they'll replace the turbos under the extended warranty.

[Zach1328]

Originally Posted by DuDai

Quick question, what are your wastegate settings at? Menu 10&12? Adjusting those a certain way can attribute to a lot of lag. I know my car has lag initially but it's due to my settings.

I'll check the settings tomorrow. I haven't intentionally messed with the settings at all and I wasn't having any under-boost issues the first couple weeks after installing my JB4.
It's possible I accidentally changed the waste-gate setting while I was learning to use the JB4, but I don't think I did.

I've been having waste-gate rattling issues though which were evident when I purchased the car and even more so after installing the JB4. Hopefully I can get some new turbo's from BMW before the car reaches 82k miles.
Otherwise, RB's might be on their way sooner than I was hoping.