Fuel issues

Sshec152

Corporal
Nov 3, 2016
213
118
0
Aston pa
I have an 07 335i st, i went to leave for work and about 1/4 mile down the road, the reduced engine power light came on and it was sputtering/misfiring horribly. I was able to limp it home, plugged in my tablet and pulled codes (2E33 - DME:fuel injector, cylinder 4, activation), 30AF - DME:fuel injector, cylinder 4, activation) and a shadow code (2FDB - fuel high pressure). I checked for continuity on injector #4 wires from the injector plug to the dme, both were good. I replaced cylinder #4 injector, no change. I had all 6 mosfets replaced a few months ago due to #6 going bad, so I decided to test them anyways, they all tested ok. Has anyone experienced this or have any ideas where to look next?
 

doublespaces

General of the Army
Oct 18, 2016
8,943
4,150
0
AZ
Ride
2009 E93 335i
I assume that the issue continues to come back immediately when you turn the car on now?
 

dyezak

Major
May 4, 2017
1,768
1,515
0
Plano TX
Ride
335is
This can only be three things really:

1. Bad Injector
2. Bad DME
3. Bad Wiring

Injectors are ruled out, DME is a maybe as you've already addressed the MOSFET's so it *should* be OK. Your wiring loom may be damaged. Water, heat, abrasion, etc. You could have continuity, but there may be an intermittent drop from wire or connector damage, or increased resistance due to corrosion or contamination. You could get lost in testing that loom, it's a nightmare. I'd buy a replacement loom on ebay for $100 and try it out.
 

R.G.

Lieutenant
Nov 17, 2016
669
325
0
Henderson, NV
Ride
E92 335, F10 M5
Log the next start up and short cruise if possible. If the issue happens after giving it 30-40% throttle then my money is on hpfp.
 

R.G.

Lieutenant
Nov 17, 2016
669
325
0
Henderson, NV
Ride
E92 335, F10 M5
Car is OL fueling. Take a pic of existing codes (for your own records), then clear them and re log start up.
 

Sshec152

Corporal
Nov 3, 2016
213
118
0
Aston pa
I will relog tomorrow after work, i also want to hook up a scope to the injector wires to see what signal the dme is sending out, if any.
I'm assuming you reprogrammed the dme when you swapped the injectors. Have you looked at the fuel feed line it's self? Might have a clog
I didn't code the injector yet, laptop screen decided to take a shit and my scanner is at work. I dont think it will make a difference but ill try that to anyways. Also good call on the feed line, ill take a look at that.
 

Kenjermen

Sergeant
Nov 6, 2016
259
78
35
N las vegas NV
I didn't code the injector yet, laptop screen decided to take a shit and my scanner is at work. I dont think it will make a difference but ill try that to anyways. Also good call on the feed line, ill take a look at that.
It could be a coding issue, the dme gets real picky on what injector you have in there
 

Sshec152

Corporal
Nov 3, 2016
213
118
0
Aston pa
Ok so i was doing more digging today. I have pretty much ruled out the wiring. I have continuity on both cylinder 4 wires, no melting, rubbing through, and resistance across both wires is the same as every other cylinder. I then checked for injector pulse on cylinder 4. If i clear the codes i get an injector pulse on cylinder 4 upon start up, then immediately goes into limp mode, throws the (2E33 -DME: fuel injector, cylinder 4, activation.) code and i lose injector pulse on cylinder 4. If i clear the DME codes with the engine running, i get an injector pulse on cylinder 4 for a split second, before the code comes back an i lose injector pulse. I also made sure the fuel line was clogged (trust me e85 taste horrible.) I've basically chase to down the dme, even though i have never changed the tune, i will try flashing back to my base map just to put my mind at ease. I have attached a log of me starting the car and allowed it to idle for about a minute before shutting it if, to see if you can see something i dont. I'm not about that msd80 life!
 

Kenjermen

Sergeant
Nov 6, 2016
259
78
35
N las vegas NV
I don't think it's a map issue, but never hurts to try. To completely rule out the injector you can swap it around and see if it follows. It does sound like a dme/programming issue.
 

Sshec152

Corporal
Nov 3, 2016
213
118
0
Aston pa
Just bought an msd81 from vadersolutions, fingers crossed that this fixes my issue, i will report back once I install it.
 
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Sshec152

Corporal
Nov 3, 2016
213
118
0
Aston pa
Just a little update, got the new msd81 from vader solutions, installed it. If anyone is wondering m, it's complete plug and play. You just unllug your old dme and plug your new one in. I then flashed it with the same tune I previously had, but converted over to IJE0S by @Twisted Tuning. I then went to fire it up and all i got was cranking, no start. I got a (2FBE - fuel pressure after engine stop) and mhd was showing 3k+ psi on the high fuel pressure sensor, when id clear it it would come right back. So I decided to crack the main fuel line after the hpfp to relieve fuel pressure and try again, but it didn't shoot out like you'd expect for 3k+ psi, it just kind of flowed out. Tighten the line back up cleared codes and again and cranked her over again. This time it started and idled with no misfire!!!! But wait it's an n54, i cant get off that easy :( now it stall after a couple of seconds and i get a code for low fuel pressure and mhd is showing exactly what my lpfp pressure is. I suspect bad hpfp, but I will have a new high fuel pressure sensor here today just to try. My car has 105k miles and i run e85, previous service records show no sign of hpfp replacement, so it's long overdue anyways.