y0itzflip

08 535i sport, completely stock, 85k miles. no warranty. car is babied most of the time

was driving the car, completely fine. went home for the night, woke up and it was shaking and misifirng,. just waiting thinking because it was colder than usual (high 80s the day before, high 40s when i went to start the car) was getting misfires on cyl 1,2,3, started to drive to see if itll go away and got the half engine light, turned around and went the half a mile back home.

switching them with 3,4,5 didnt move, change plugs, still same thing. (just to note, plugs 1-3 looks really black compared to 4-5 which looked basically new, since they were changed not too long ago)

ran the car in inpa (usually use generic scanner, and clear before every restart while i had this issue)


i have pasted the only codes in the system

12 DME/DDE OKAY 5 Error stored
30BA 61
29CD 92
29CF 92
29CE 92
29CC 92

i read that it could possibly be the fuses in the ecu box, i am about to check those now (if i can ever get the little cover off the fuse holder), but just posting up in case somebody else may have had this issue before. car is out of warranty, so all out of pocket time. if it is dme (if i have the one that is prone to issues), ill have to find somebody to order the mosfets and replace hopefully

sorry for the long post, just wanted to answer any questions before they were asked.

opinions?

seanjordan20

Have you changed any injectors if sot it could be that. if not check the MOSFETs. That is were I would start since it is a known issue. Its cheaper than replacing the DME.
This video shows you how to do the test if you are good with circuit boards

seanjordan20

I found this on ebay just to give you an idea. I have no idea what it cost to change out a DME but I would look at doing a service like this.

Amish

I just had to deal with my own DME last week. I has a misfire on 6. Melted my coil. It was the #6 transistor/ mosfet on the DME. I ordered 10 from Mouser Electronics for 2.29 ea. I found a local electronics shop to solder for me. 100 bucks and she's running great. Atlas Electronics in Dallas.

seanjordan20

What DME do you have and what was the part number you bought from Mouser Electronics. This information will help him out if he decides to repair it himself. By the way Mouser has always been my go to when it comes to electronic repair.

y0itzflip

i went ahead and ordered the mosfets. im pretty sure thats what is after doing a lot of reading, and the fact i have the dme that is known to have that issue. been a long time member, always found what i needed via search lol. sucks that i had to make this post. they will be here weds, hope to swap out same day. will update thread.

ordered 10 from here

FDB14N30TM Fairchild/ON Semiconductor | Discrete Semiconductor Products | DigiKey

thanks guys

y0itzflip

just an update, tested the dme, all mosfets test fine. so im guessing injectors? is it common that all 3 injectors would go bad at once or could it be something else in bank 1

NoQuarter

I would lean more towards the DME problem than 3 injectors going bad at once.

Maybe replace the MOSFETS anyway. You already have them. You got nothing to lose here.

seanjordan20

+1

y0itzflip

im going to have somebody do the replacement today. i just find it weird that they all test good. kinda hard to explain to somebody when they ask "what made you come to the conclusion that they need to be replaced and they all test fine?"

lol