Help With Limp Mode, Misfire and 30FF - JB4tech.com

e36luv · 08:04 AM

I have been searching and I have made attempts to sort this on my own. My car starts up fine but under throttle it starts to stumble and wont hardly move.
I am getting the Engine Malfunction Reduced Power along with these codes through the JB4:
29D1 Misfirings, cylinder 5
29D2 Misfirings, cylinder 6
29CC Misfirings, several cylinders
29D0 Misfirings, cylinder 4
30FF Boost under target -- possible boost leak
I have also had 2AAF fuel pump, plausibility but that is not currently coming up.

My car is stock besides the JB4 on MAP 1. I have replaced all of the vacuum lines, replaced the ignition coils, spark plugs and checked the chargepipe for leaks. What is next? I dont want to just throw parts at it but I am thinking the injectors/HPFP next

08335ibmw · 07-10-2016, 03:15 PM

New plugs if they havnt been changed, check charge pipe they tend to get brittlw and break

08335ibmw · 07-10-2016, 03:16 PM

Post logssssss

08335ibmw · 07-10-2016, 03:16 PM

My phone wint pull up the link

Showdown045 · 07-11-2016, 12:12 AM

I had the exact same issue and also a strong smell of fuel. New plugs and Walnut Blast fixed the problem.

e36luv · 07-11-2016, 08:04 AM

Log added to the original post

e36luv · 07-11-2016, 09:53 PM

I checked tonight and my car has the MSD81 DME, I haven't heard about any MOSFET issues with the 81. What else could be causing cylinder 4,5,6 misfire and the way this thing is running? I removed the jb4 and will test drive it in the morning to see if anything changes

anyone have any other ideas?

Jsr1256 · 07-12-2016, 01:37 AM

My buddy's car did that because he didn't unhook the battery when he installed the jb4. Try unhooking batt wait 35min leave keys far away just incase don't open any doors etc try reinstall

e36luv · 07-12-2016, 06:38 AM

Quote:

Originally Posted by Jsr1256

My buddy's car did that because he didn't unhook the battery when he installed the jb4. Try unhooking batt wait 35min leave keys far away just incase don't open any doors etc try reinstall

I just drove the car with the jb4 removed and nothing changed. It ran fine for the first 5k or so mile with jb4 installed also

Jsr1256 · 07-12-2016, 08:52 AM

Man that sucks, only thing I can think of is what you stated injectors and hpfp get some BMW injector cleaner maybe that will solve any issues with injectors. Worked for me. I can't look at your log cause I'm on my phone but what is the hpfp number at

08335ibmw · 07-12-2016, 04:52 PM

I got the 30bb code today and cylinder 4,5,6 misfire dead dme per bmw

Jsr1256 · 07-12-2016, 05:24 PM

Ouch! I wonder how that happens possibly jb4 install gone wrong?

08335ibmw · 07-12-2016, 05:37 PM

Jb4 was out in 6 months ago , n54dme dan said that bmw mofets are barely keeping up with bmw stock tune , said once you change a tune no matter jb4 cobb or dinan it pops mofets . So im guessing its just a issue no matter if your upgrading or not bc i hear about stock bmws doing same thing

08335ibmw · 07-12-2016, 05:52 PM

Mines a 2008 most happen with the 2007 dme idk if mine was a 2007 build date though

Jsr1256 · 07-12-2016, 06:19 PM

Mine is a 6/08 build date I would ask Terry about it, maybe it is crashed or maybe it's just a fluke. I dno if this will work. You can try the flash back to stock with mhd it will build you a stock flash bin. I dno if your ecu has a glitch in the software or if something actually burnt up. Deff ask Terry before you take that advice tho. You could find someone to do a bench flash with winkfp too

Jsr1256 · 07-12-2016, 06:51 PM

I didn't see your previous response. Let me.know how it goes on replacing them. Goodluck

08335ibmw · 07-12-2016, 06:55 PM

Terry replied to a post about my situation and said i should bring it to a mechanic that could read the codes or somthing to that,affect . I think it was steve that pointed out it was most likely the mofets . I thank both of them for there time and replies

e36luv · 07-13-2016, 08:37 AM

So I reinstalled the JB4 last night and took the car for a drive this morning. I waited for it to warm up and then beat the crap out of it in 3rd gear and it did not go into limp mode this time but still didn't run 100%. Only codes I got this time were mifire cylinder 4 and fuel pump plausibility. At some point the car switched to map 4.
Here are the logs i took, one is in map4. The fuel pressures look good to me in the map so can i rule out the fuel pump?

I am trying to get a INPA cable so i can swap injectors around and see if the problem follows.

What do you think?

08335ibmw · 07-13-2016, 08:54 AM

Mabey coilpack

Jsr1256 · 07-13-2016, 08:56 AM

I won't be around my comp till later today I'll look at them and see if anything stands out. In the mean time hopefully someone else will chime in.

Jsr1256 · 07-13-2016, 09:16 AM

Also enable your 6cyl timing in your user setting on jb4 app it's probably a 4 but try 5 too

E92wala · 08-23-2016, 02:25 AM

Any update? Did you fix the problem and how?