[parylizer]

Hi, I just recently installed the JB4 to my 07 335xi and did some logging yesterday to make sure it was all running properly. I have been noticing on the boost gauge (fuel gauge) and in my logs as well that my car seems to take a very long time to reach the maximum boost around 13PSI. I have no other mods just the JB4. I also recently had the car in at the dealer before i installed the JB4 because I was not getting any boost at all and they checked over all the lines and replaced one hose and also a sensor. I am not sure what else this could be anybody have any ideas? I attached one of my logs that i was running map5 to show what I mean. You can see it took nearly 4 seconds to reach max boost around 12-13psi but it should be only taking second or two at most. This was a 3rd gear pull from 2k rpm to 7k rpm. Also when i just punch it ( I have an auto) and it downshifts and the rpms jump to 4k ish the boost seems to build up very quickly as it should, it just builds very slowly when i do a pull starting at lower rpms. Anybody have any ideas?

[nvn]

When you floor it, don't push the pedal all the way down. On AT cars, there's a kick down switch that will downshift if you hit it. You can still go WOT without the pedal all the way down, just gotta get the feel for it or do a kick down blocker.

DIY here

http://www.n54tech.com/forums/showth...light=kickdown

[parylizer]

Originally Posted by nvn

When you floor it, don't push the pedal all the way down. On AT cars, there's a kick down switch that will downshift if you hit it. You can still go WOT without the pedal all the way down, just gotta get the feel for it or do a kick down blocker.

DIY here

http://www.n54tech.com/forums/showth...light=kickdown

Not sure you read the thread... I know about the kick down that's not the issue. My turbos seem to be spooling up very slowly as you can see in the log and am wondering if anyone knows what may be causing this.

[nvn]

Originally Posted by parylizer

Not sure you read the thread... I know about the kick down that's not the issue. My turbos seem to be spooling up very slowly as you can see in the log and am wondering if anyone knows what may be causing this.

The boost builds faster after you hit the kickdown is because the revs are higher and it downshifted. Try starting your WOT run around 2500-3k. Starting at 2k or lower, the boost will build slow like your log shows. I mentioned the kickdown so you wouldn't run into that problem doing a log.

[georgelb]

As was said, 2k RPM isn't in your "Wheeeeee!" power band.

[parylizer]

Originally Posted by georgelb

As was said, 2k RPM isn't in your "Wheeeeee!" power band.

I understand that but if you look at a "normal log" I should be reaching full boost in 1-1.5s and it is taking me 4s+ to get to that point. I have spoken with Terry from BMS and he was the one who pointed it out to me that my car is spooling very slowly. I am just wondering if anybody has had a similar experience and knows the problem or any ideas and what the cause could be?

[jaykayelemenohpee]

Why do you keep letting of the gas?

[parylizer]

Originally Posted by jaykayelemenohpee

Why do you keep letting of the gas?

Hmm not sure why throttle has dips, i didn't let off at all and you can see the graph for the pedal (not throttle) is at the top whole time.

[themyst]

Originally Posted by parylizer

Hmm not sure why throttle has dips, i didn't let off at all and you can see the graph for the pedal (not throttle) is at the top whole time.

throttle is dipping because boost is overshooting target and the JB4 is closing throttle to keep the excess airflow from entering.

[themyst]

and OP, increase your lagfix (Wastegate position).

[parylizer]

Originally Posted by themyst

and OP, increase your lagfix (Wastegate position).

1st post- Ok i was running map5 so maybe that is why, I will run some logs running map 1 and see if the throttle is steadier.

2nd post- Thanks I will give that a try and update!

Update: tried wastegate position at 100 and it still seems to build boost slowly when doing a WOT pull in 3rd from 2k-7k rpm. I will have to make a log to see for sure if it helped but any other ideas? Its definitely still slower then it should be.

[themyst]

Originally Posted by parylizer

1st post- Ok i was running map5 so maybe that is why, I will run some logs running map 1 and see if the throttle is steadier.

2nd post- Thanks I will give that a try and update!

Update: tried wastegate position at 100 and it still seems to build boost slowly when doing a WOT pull in 3rd from 2k-7k rpm. I will have to make a log to see for sure if it helped but any other ideas? Its definitely still slower then it should be.

vacuum leak, tired wastegate solenoids, could be a number of things. Repost log with PWM.

[parylizer]

Originally Posted by themyst

vacuum leak, tired wastegate solenoids, could be a number of things. Repost log with PWM.

Thanks I will do that today, what is PWM for?

[parylizer]

Originally Posted by themyst

vacuum leak, tired wastegate solenoids, could be a number of things. Repost log with PWM.

Oops didn't realize I could just add PWM to the current log so I did a few more logs. I did runs from a stop and a 3rd gear pull in both map5 and map1 then also a 3rd gear pull in map4 (stock). I can post these as well if it helps but here is the original + PWM.

[Jeff@TopGearSolutions]

Since JB4 logs are something from the 90's try using this program to upload logs.

http://www.datazap.me/

This should be the new standard of logs as it's a great tool and easier to read.

[parylizer]

Originally Posted by Jeff@TopGearSolutions

Since JB4 logs are something from the 90's try using this program to upload logs.

http://www.datazap.me/

This should be the new standard of logs as it's a great tool and easier to read.

Ok heres the log on that site:

http://www.datazap.me/u/parylizer/slow-spooling?1-3-4

Just look starting in the middle, that where the run starts.

[themyst]

Originally Posted by parylizer

Oops didn't realize I could just add PWM to the current log so I did a few more logs. I did runs from a stop and a 3rd gear pull in both map5 and map1 then also a 3rd gear pull in map4 (stock). I can post these as well if it helps but here is the original + PWM.

Attachment 912501

Yeah, your PWM is in spool mode for a bit longer than I'd like, especially if lagfix is at 100, but once at target PWM is normal.

I would point to vacuum leak or bad wastegate solenoid. Boost leaks you'd see elevated PWM regardless of boost, which you do not have.

Do this DIY on Terry's site... This appears to be a G4 board based on the PWM cap being very low in spool mode. You should see something like 17-19" of vacuum at idle. Or you could consider upgrading to G5 ISO as the PWM cap is much higher. It's kind of putting a band-aid on a cut though, it may fix your spooling issues but there's still a likely issue that needs to be addressed.

http://www.n54tech.com/forums/showthread.php?t=16548

[parylizer]

Ok thanks I will try that test and update.

[parylizer]

Originally Posted by themyst

Yeah, your PWM is in spool mode for a bit longer than I'd like, especially if lagfix is at 100, but once at target PWM is normal.

I would point to vacuum leak or bad wastegate solenoid. Boost leaks you'd see elevated PWM regardless of boost, which you do not have.

Do this DIY on Terry's site... This appears to be a G4 board based on the PWM cap being very low in spool mode. You should see something like 17-19" of vacuum at idle. Or you could consider upgrading to G5 ISO as the PWM cap is much higher. It's kind of putting a band-aid on a cut though, it may fix your spooling issues but there's still a likely issue that needs to be addressed.

http://www.n54tech.com/forums/showthread.php?t=16548

Hey, I did terry's test and my results were definitely not as they should be. I set future use d to 99 and when I rev the engine i only get about 12-13 in. and then at idle after the rev it drops to almost none around 2-3 inches. I also noticed that PWM does not go up to 100 like terry shows in his video it stays at 0.

[themyst]

Originally Posted by parylizer

Hey, I did terry's test and my results were definitely not as they should be. I set future use d to 99 and when I rev the engine i only get about 12-13 in. and then at idle after the rev it drops to almost none around 2-3 inches. I also noticed that PWM does not go up to 100 like terry shows in his video it stays at 0.

either vac leak or bad wastegate solenoids. smoke test the system to find the cause.

[parylizer]

Originally Posted by themyst

either vac leak or bad wastegate solenoids. smoke test the system to find the cause.

Is there a guide on how to do that. Although is there anyway I could find the cause other then that. I dont own nor know anyone with a smoke machine.

[parylizer]

UPDATE:

Now I have an even bigger problem but perhaps it will help identify the issue though. Now I am producing 0 boost and got a engine light with the 30ff code boost under target possible boost leak. I did a log and from what I can see both boost and PWM are both non existant. Does this mean its the solenoids? Or maybe a vacuum line that popped off / leaking enough to create no vacuum?

Here is a log.

http://www.datazap.me/u/parylizer/ze...-and-30ff-code