[maddmatt02]

ok, I already had installed a JB4 in my car a while back but came across a combo on here that I couldnt pass the deal up. today I swapped in the harness and JB4 I just bought and it runs fine, no codes, features like warm-up flash, dtc toggle, guage hijacking, etc work fine, but the car wont build boost. I have boost on fuel and my fuel gauge just sits at 0 for the whole pull, logged 2nd gear and it was targeting 14.1, boost was 0.

all I had to do to fix it was re-install my old JB4 into the new harness and it works so I know the problem isnt a connection with the ECU.

I emailed him saying it didnt work but figured might as well give him the benefit of doubt thinking maybe theres a setting I dont know about that could cause it. I thought I mirrored the settings that were what I was running on mine. also was running the newest firmware and diodes were cut.

I think its got to be the JB4 itself (enclosure deformed from heat, board looks a little toasted by the 2 resistors side by side at the edge, but the resistors themselves dont "look" burnt up. also it smelled like hot electronics when holding it after I swapped them out.

http://www.datazap.me/u/maddmatt02/l...log=0&data=1-4

[Mike@N54Tuning.com]

any codes being thrown? The car runs normally?

Mike

[335NJ]

Screenshot the current user settings in the interface.

[maddmatt02]

now Im thinking something is wrong with the connection also, just tried to do a quick log with my old jb4 back in with the new harness and I know the car is building boost, seems like it feels a little different than Im used to but I did update my bms pump backend today as well so maybe thats it. but from driving it, and then looking at the log it seems like thats not really what was happening... was wet though so Ill try and get one next time its dry out here. earlier when it was dry, my boost on fuel gauge was showing peaks around 13-14 id say but I wasnt logging back then on my original jb4.

http://www.datazap.me/u/maddmatt02/l...4-9-13&mark=37

[maddmatt02]

it threw 2abd, somehow the n20 map option was 15 (when I first opened it that and timing logging were both 15, thought Id saved them at 1 and 4 but after I got the code, and it referenced the map reading, I checked again and I must have forgot to save it. my code reader kept saying no codes and i had to have the car running and use the jb4 to read it while it was running and I had selected 1/4 to disable autoclear in case it was enabled but it didnt help, that right there stumped me a bit. but after I cleared it and updated the n20 map value it never came back. both my reader and jb4 said no codes. I would have to reinstall the other jb4 to get the screenshot but I know that I clicked no or all the FUD "bits", nothing in FUA, N20 map 1, timing 4. all afr bias was 0, all duty bias was 65,


just copied these settings over from this page where terry goes over tuning those values - boost safety was 20, default wastegate position 60, PID gain 25, shift boost reduction 60, ff 50, fuel open loop 40.
- http://www.n54tech.com/forums/showthread.php?t=29893 I figured they wouldnt be perfect but that they would at least "work" good enough to test it out.

but yes, other than being slow and not building boost, seemed to start and idle fine, crusing around the neighborhood at 15-20 you didnt know anything was wrong...

[unrealii]

When I installed my JB4 (I bought used), my car was throwing underboost codes. Turns out the waste gate position was modified by previous owner, so after correcting that in the jb4 interface, I was good.

Burger doesn't provide much support for used JB4s. I found out the hard way when I tried to diagnose this issue and another. I ended up cashing out. If I ever decided to go back to JB4, I would only buy new

[maddmatt02]

I changed the default wastegate position as well as tried adjusting it with the steering wheel. the case was warped but the board itself didn't look too bad, but I'm betting some components are damaged.

google doesnt let me link photos here I guess, so heres a link to an album with the photos of the JB4

https://goo.gl/photos/Zx17kAKey7M8CrNy8

[maddmatt02]

finally got to play with the car in the dry yesterday and its fine. must have just been the dtc/throttle closures that made it feel so different when I first plugged my jb4 in the new harness(was really wet out). so now Im sure I have a bum board, still havent heard from the seller but Ill give it a few more days before I start worrying, he could be on vacation or something...

[Sered]

Originally Posted by unrealii

Burger doesn't provide much support for used JB4s. I found out the hard way when I tried to diagnose this issue and another. I ended up cashing out. If I ever decided to go back to JB4, I would only buy new

The hell they don't. BMS doesn't care where you got your unit from whether new or used. They don't ask for serial numbers, receipts, or anything for that matter. Just logs and information. Stop spreading misinformation.

[unrealii]

Originally Posted by Sered

The hell they don't. BMS doesn't care where you got your unit from whether new or used. They don't ask for serial numbers, receipts, or anything for that matter. Just logs and information. Stop spreading misinformation.

My statement is based off of personal experience. Additionally, two of the top forum vendors have corroborated what I have stated.
http://www.e90post.com/forums/showthread.php?p=19316640

Stop spreading misinformation misinformation.

[wtfmateim65]

I just ran into this EXACT same issue. Car was running fine at 18psi then next drive I go on ZERO boost. Checked all vac lines and connections and finally ran into some random posts about similar issues so checked the ECU box. JB4 enclosure was warped from heat on one side and those same two transistors looked toasted at the contacts.

Terry said this is a known issue with older jb4 boards. Had to shell out $175 for a replacement board, hopefully it solves the problem when I get it next week.

[theweebabySeamus]

Originally Posted by unrealii

When I installed my JB4 (I bought used), my car was throwing underboost codes. Turns out the waste gate position was modified by previous owner, so after correcting that in the jb4 interface, I was good.

Burger doesn't provide much support for used JB4s. I found out the hard way when I tried to diagnose this issue and another. I ended up cashing out. If I ever decided to go back to JB4, I would only buy new

BMS helped me with diagnosis on my used jb4 on a Sunday (Mothers day no less) within about an hour. I wouldn't blame them if the above was true but it has been anything but in my case.

[maddmatt02]

Board ended up being bad but they helped me out more than I'd expect them to. Great service.

[unrealii]

Originally Posted by theweebabySeamus

BMS helped me with diagnosis on my used jb4 on a Sunday (Mothers day no less) within about an hour. I wouldn't blame them if the above was true but it has been anything but in my case.

Thats great that he did the right thing. Seeing all the posts of BMS taking care of used jb4 owners, set the expectation that I should have been taken care of, but that didn't happen. I dont blame BMS because its a used product. We shouldn't be setting the expectation to users that buying used that BMS will handhold and help diagnose every problem that they encounter.