[Montego_D]

09 335D with 70k miles, all recalls done as well as CBU service done two years ago. Drive to the Bay Area 3x a week so 90% of miles are highway, trips averaging 120 miles each way. Battery is in great shape, and has been disconnected for 3 days, as well as codes reset using BavTech, INPAS/DIS.

If you do a search you will find there are more problems EXACTLY like mine which have gone unresolved or forum members blast the person for taking it to a dealership with codes still onboard. Understand that these codes cannot be reset with any software we use...

I had the exact same issue with the exact same box last year and ended up having to replace the fuel rail pressure sensor, but this time before I reinstalled the unit I sent it in to Burger to be checked and have the potentiometer replaced as it had no 0 or 100 stops. They bench tested it as being fine.

Plugged it in 3 weeks ago (without entering sleep mode, my bad) and the dash lights up like a Christmas tree so I immediately turn off the motor and disconnect unit. Trying to troubleshoot it was actually drive-able with the half yellow motor Limp mode, and SES light on with these codes:

Engine / Motor
>>>> Rail pressure sensor
>>>> Code: 003F30

>>>>
>>>> DDE main relay
>>>> Code: 004121

Replaced the main relay first, this time entering sleep mode as well as disconnecting battery first. Cleared the DDE relay code and it has stayed gone.

Others have suggested "contact Terry at Burger, he is responsive and the customer service is excellent"... yes he is responsive. His three responses to my request for help, acknowledging that I could likely have done something wrong, were not so excellent:

1)sorry, the codes done really indicate something is wrong with the FP which the module adjusts... WTF? I am pretty sure that the module that the JBD plugs into is saying its bad, an oh yeah its the second one I have replaced after running your module.
2)sorry but it tested ok on the bench you will need to have a technician help for further diagnosis.
3) picture you sent is fine, the install was correct. Consult with tech.

For someone who is an expert in the field, his responses were far worst than expectd I would ever get... what do you mean the codes do not represent anything you modify? I thought you fooled the sensor which it plugged into for higher fuel volume/pressure?

I ordered a new and after putting car into sleep mode, and unplugging battery, installed and tried to start car. Things at this point get worse because with the previous sensor the car would at least drive, now it wont start at all. Using DIS the hpfp will prime so I assume its ok... or hope so anyway. Fuel filter is new, oil is correct spec and changed every 7500 miles.
Now I get a no start and these codes:

3F30 DDE: Rail-pressure sensor, signal - open or short circuit to positive

4121 which is a result of the test protocol DIS puts it through and it clears

4B90

I changed the sensor to the one taken out and the car still turns over and wont start.... crap. FML.

There is sits, being stubborn not taking it to my buddy who is the head tech at the dealership.... his home garage is sweet.

Any help is greatly appreciated, sorry for the wordy post, but I wanted to provide enough info for some solid answers.

Oh, last thing when going through the test schedule in DIS and attempting to start the car for a senor reading, it goes to:

Compare target value and actual value.

Setpoint:
Rail pressure = 0 +/- 26 bar

Actual value, rail pressure : 400 bar

While cranking the pressure will raise to 426 bar...

Thanks!

[Built4Sin]

Not an expert, but just relaying how my install went.

Got the unit, popped the hood, disconnected the fuel rail control connector and then seated the JBD connector and zip tied the control box by the power steering box.

I never disconnected the battery, let the car sleep or anything else.

I do get the fuel rail code, if I don't let the car warm up a few minutes before going WOT. I'll get a limp code that cuts power however I then use Carly seconds later to clear the code while driving. (Don't code and drive kids!)

Are you sure your connecting to the right plug in the engine bay?
Are you sure the plug is fully seated?

Good luck! It blows that you're having this much trouble with what usually is error free.

[Montego_D]

Thanks for the input Built. I did try the zip tie route when initially started, so connections were solid. Took a picture of the install and Terry at BMS said it was installed correctly and take it to a mechanic. Carly wont reset the codes which come up on mine...


Anyone with some sagely advice?

[gavronm]

I had to take mine on and off a few times and wasn't as careful as I should have been and pulled one of the JBD connector wires loose. Would start but ran like garbage. Found the loose wire, fixed it, no more problem.

I would do a very careful very thorough check of all the wires going into the OEM connectors.

[WreckerX5d]

Check continuity on all connections with a multimeter.

[Montego_D]

Thank you both... Started down that path until I then had to question my new meter, so going to grab a spare tomorrow. Did I mention that I had locked my keys in said car this week as well? It's just been one of those experiences.

Will post results tomorrow, thanks again.

[Montego_D]

Here I was hoping that troubleshooting 101 would lead me to the light at the end of this dark tunnel. Any of those genius forum gods care to chime in on this? Your wisdom is greatly appreciated... It's going on 3 weeks and ready to push the car off the cliff.

Reflash after this and never again looking for the simple way to do things....

Thanks in advance.

[gavronm]

Maybe don't give up on the easy solution just yet. Did you give each individual wire a little tug to see if it's loose? Jamming a multimeter probe into the back of a connector will push a loose wire into place and give you a positive test but as soon as you start the engine and things start vibrating you'll get an intermittent connection.

Good luck.

[Montego_D]

Not just the imaginations of a Silicon Valley tech guy rambling in the forums... Several came out with exact same issue and codes in this thread

http://www.e90post.com/forums/showthread.php?t=662854


I strongly suggest to anyone contemplating this path to reconsider a piggyback box that simply changes one thing, especially for a market so small. The guys at Burger made their money, have no further development (or support) and it's all margin at this point.

I have a JBD FOR SALE CHEAP... $80 lol.

It's going on the flat bed tomorrow to my independent, as I can't stand it sitting in the garage... Oh yeah and I went an picked up a 2014 Lexus CT200h to join the land of one person commuter cars lol.

FML

[WreckerX5d]

The JBD is such a simple circuit. It's just 2 resistors, 2 capacitors, 1 potentiometer and an integrated chip.

I toyed around with my JBD by swapping different resistors around to drop more voltage. I found that the fuel rail is super sensitive and it will not engage the fuel to start the car if it's out of the slightest specs. I think I read somewhere on here that there's a tolerance of .5 VDC.

BMS did an 'updated' version of it and it could be out of parameters upon a certain setting on the pot. Or you could have an open somewhere.

[Barmlot]

Another disappointed JBD user here. My car would start fine and then after about 3-5 days of using it would get TERRIBLE rough idle. Checked all the connections everything is fine. I too had posted about my jbd problems on this board and all you seem to get is "let it warm up" and "mine works fine, been using it for years" "you must be doing it wrong" oh well, it really isn't needed IMO, but was fun. I decided it was not worth the risk after it gave me trouble on a highway. Probably got a "bad" one or somesuch

[Montego_D]

Thanks Wrecker335d, one of my diag programs actually lists it as an open...

3F30 DDE: Rail-pressure sensor, signal - open or short circuit to positive


Can you assist with some troubleshooting advice and where to start? I have a diagram that shows the pin outs for the sensor.

Thanks!

[Thecastle]

I'm just going to mention, I've had my jbd fail. So don't rule out the possibility of a bad jbd.

I had been using mine successfully for months and thousands of miles. Turned the car off one day. Turned it back on and it ran like crap, half engine light appeared, and it had the power of an old weed whacker. Tried cycling the car on and off, and even driving it a little bit, it's hard to move a 4000lbs car with 3 cylinders haha.

I pulled the codes and had 7 related to fuel rail pressure and fueling. Pulled the jbd out and the car ran fine. Reset my dde and no problems since the jbd was removed.

Btw I was about to crap myself when this happened. I was in big bend national park, and was 350 miles out of my cars native habitat which is in the service bay of a BMW dealer. So I think she just got scared being so far away from a mechanic hahaha. Imagine the tow fees, if you've never been there big bend is really out in the middle of no where, and break downs are very expensive.

Anyway had to borrow tools from the campground care taker to pull the engine cover off and remove my jbd.