Post Reply 
 
Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
Misfiring on cylinders 1-3.
01-04-2018, 05:22 PM
Post: #1
Misfiring on cylinders 1-3.
Good day, I'm getting a misfire on my first 3 cylinders. I have checked spark plugs, coils and even injectors. I've swooped out the spark plugs from 1 2 and 3 with those of 4 5 and 6. But the problems still stay with 1 2 and 3. I have swapped the coils in the same manner as well as injectors and the misfire stays in those three cylinders. The first three have no change in idle whether I unplug the coil or injector. Please assist. It's a 2007 N54. No mods on the vehicle at all.

Regards
Sechaba.

Sent from my PRA-LA1 using Tapatalk
Find all posts by this user
Like Post Quote this message in a reply
01-04-2018, 06:10 PM
Post: #2
RE: Misfiring on cylinders 1-3.
Best to check codes and list them here in totality. I suspect a DME injector bank 1 PSU fault in there somewhere.

PMs don’t work, so if I don’t reply I’m not being rude.
Find all posts by this user
Like Post Quote this message in a reply
01-04-2018, 07:45 PM
Post: #3
RE: Misfiring on cylinders 1-3.
(01-04-2018 06:10 PM)Ratslaaf Wrote:  Best to check codes and list them here in totality. I suspect a DME injector bank 1 PSU fault in there somewhere.
I'm using OBD check with the elm 327. But this is what I found. [Image: fa0820740c64bca678a4b3e30bfe3c16.jpg][Image: 1b806992073d4b6274647b07ee5411bd.jpg]

Sent from my PRA-LA1 using Tapatalk
Find all posts by this user
Like Post Quote this message in a reply
01-04-2018, 08:03 PM
Post: #4
RE: Misfiring on cylinders 1-3.
Hmmm, that ones a little weird. I’m assuming the pending fault are where you’ve disconnected injectors while the car was running?

I’m leaning towards bank 1 injector power supply in DME, but would wait for advice from the N54 experts. It might also be an O2 sensor acting up that’s interfering with mixture control.

PMs don’t work, so if I don’t reply I’m not being rude.
Find all posts by this user
Like Post Quote this message in a reply
01-04-2018, 08:09 PM (This post was last modified: 01-04-2018 08:12 PM by Schabzo08.)
Post: #5
Misfiring on cylinders 1-3.
It's been giving me a headache all day because it is just running on 3 cylinders.

Sent from my PRA-LA1 using Tapatalk

(01-04-2018 08:09 PM)Schabzo08 Wrote:  It's been giving me a headache all day because it is just running on 3 cylinders.

Sent from my PRA-LA1 using Tapatalk
DME being the control unit?

Sent from my PRA-LA1 using Tapatalk
Find all posts by this user
Like Post Quote this message in a reply
01-04-2018, 10:42 PM
Post: #6
RE: Misfiring on cylinders 1-3.
Dude U got a n54 use mhd to read codes it's much better.

Current: 2008 E92 335i
Sold: 2004 BMW 325ci
Find all posts by this user
Like Post Quote this message in a reply
The following 1 user Likes NAS325ci's post:
bmw335ie90
02-04-2018, 12:26 AM
Post: #7
Misfiring on cylinders 1-3.
I will try that in the morning. Thanks for the advice


Sent from my PRA-LA1 using Tapatalk
Find all posts by this user
Like Post Quote this message in a reply
02-04-2018, 03:24 AM
Post: #8
RE: Misfiring on cylinders 1-3.
Hi,

I see you tried sending me a PM, but I can’t reply as the forum seems broken. Best to get a lockset from a friend to test in your car to see if the DME is the cause of the issue. If it is the cause then I can replace, but it’s not cheap. Hence my suggestion to try another set in your car before paying for a replacement.

PMs don’t work, so if I don’t reply I’m not being rude.
Find all posts by this user
Like Post Quote this message in a reply
02-04-2018, 08:31 AM
Post: #9
Misfiring on cylinders 1-3.
I don't really have friends that have a bmw 335i. (I guess I need new friends). I'm in the East Rand next to Carnival City. Maybe someone on here can assist with proper logging.

Sent from my PRA-LA1 using Tapatalk
Find all posts by this user
Like Post Quote this message in a reply
02-04-2018, 09:48 AM
Post: #10
Misfiring on cylinders 1-3.
Rastlaaf I hope it's not the DME. I'm an auto electrician so I'm going to check for power supply and compare from the working cylinders to the non working ones. Weird this is when I removed the spark plugs from cylinders 1-3 to check for actual spark, they were wet wit fuel.

Sent from my PRA-LA1 using Tapatalk

Find all posts by this user
Like Post Quote this message in a reply
02-04-2018, 11:05 AM (This post was last modified: 02-04-2018 11:06 AM by bmw335ie90.)
Post: #11
RE: Misfiring on cylinders 1-3.
(01-04-2018 08:03 PM)Ratslaaf Wrote:  Hmmm, that ones a little weird. I’m assuming the pending fault are where you’ve disconnected injectors while the car was running?

I’m leaning towards bank 1 injector power supply in DME, but would wait for advice from the N54 experts. It might also be an O2 sensor acting up that’s interfering with mixture control.

I recently had a similar problem with my n54 and fixed a few things before i ran codes via MHD and found the bank 1 o2 sensor to be the problem. It made my bank one (cyl1-3) miss sometimes. I went and replaced it and loaded mhd on problems are gone! now shes just a beasty Thumbs
Find all posts by this user
Like Post Quote this message in a reply
02-04-2018, 03:18 PM
Post: #12
RE: Misfiring on cylinders 1-3.
(02-04-2018 11:05 AM)bmw335ie90 Wrote:  
(01-04-2018 08:03 PM)Ratslaaf Wrote:  Hmmm, that ones a little weird. I’m assuming the pending fault are where you’ve disconnected injectors while the car was running?

I’m leaning towards bank 1 injector power supply in DME, but would wait for advice from the N54 experts. It might also be an O2 sensor acting up that’s interfering with mixture control.

I recently had a similar problem with my n54 and fixed a few things before i ran codes via MHD and found the bank 1 o2 sensor to be the problem. It made my bank one (cyl1-3) miss sometimes. I went and replaced it and loaded mhd on problems are gone! now shes just a beasty Thumbs
MhD works only via cable or Bluetooth as well?


Sent from my PRA-LA1 using Tapatalk
Find all posts by this user
Like Post Quote this message in a reply
02-04-2018, 03:59 PM
Post: #13
RE: Misfiring on cylinders 1-3.
Odb cale as far as i know
Find all posts by this user
Like Post Quote this message in a reply
02-04-2018, 07:20 PM
Post: #14
Misfiring on cylinders 1-3.
I do not have one. I guess I need to find one. And quick

Sent from my PRA-LA1 using Tapatalk
Find all posts by this user
Like Post Quote this message in a reply
02-04-2018, 07:23 PM
Post: #15
RE: Misfiring on cylinders 1-3.
Bud, you might have to replace ecu and then you’ll have an issue with mhd because of a vin mismatch. I don’t currently have an N54 lockset else I would’ve lent you one, but best is to try and get another one to exclude the ecu as an issue.

PMs don’t work, so if I don’t reply I’m not being rude.
Find all posts by this user
Like Post Quote this message in a reply
03-04-2018, 08:31 AM
Post: #16
Misfiring on cylinders 1-3.
If it is the control unit, can it be repaired? Also say I have an issue with my o2 sensor on bank 1 if I physically swap it out with the o2 sensor on bank 2. Would that also maybe not give an indication of where my problem lies? Ie the problem should jump to bank 2? Or I should have a complete engine misfire due to the sensor misreading on bank 1? Or have a lost the plot here? Lastly is there a trusted place that does Ecu testing around Johannesburg or the East Rand?

Sent from my PRA-LA1 using Tapatalk
Find all posts by this user
Like Post Quote this message in a reply
03-04-2018, 09:05 AM
Post: #17
RE: Misfiring on cylinders 1-3.
I currently don’t have a jig to test the msd81 ECUs. Hence the suggestion that you try another set.

It’ll also be a good idea to swop the pre cat O2 sensors to see if the problem moves.

PMs don’t work, so if I don’t reply I’m not being rude.
Find all posts by this user
Like Post Quote this message in a reply
03-04-2018, 01:37 PM (This post was last modified: 03-04-2018 01:40 PM by Schabzo08.)
Post: #18
Misfiring on cylinders 1-3.
Mine is a MsD 80. But I wanted to try the swapping as well. But removing the sensors to test them is pain.

Sent from my PRA-LA1 using Tapatalk

What about the post cat sensors? Also do you have any idea how the system will respond if I open circuit all the 02 sensors? Any past experience with that?

Sent from my PRA-LA1 using Tapatalk
Find all posts by this user
Like Post Quote this message in a reply
03-04-2018, 01:47 PM
Post: #19
RE: Misfiring on cylinders 1-3.
Schabzo08

The Mosfets on the MSD80 DME's do fail and an easy way to test is with a multi meter.

See youtube vid below:

https://www.youtube.com/watch?v=P0_hFbNs...e=youtu.be

Give it a try first, its free and will confirm if your DME may be at fault.

If it is the problem, you should be able to source replacement Mosfets and have them resoldered on.

Goodluck, I hope you come right

2012 Imperial Blue F30 335i - Stock Standard

Ex: Space Grey 2010 135i N54,BMS DCI, JB4 with Cobb CP, MHD BEF, Fuelit Stg 2 lpfp, XHP Stg 3 Gearbox flash - 354kw 692nm
Find all posts by this user
Like Post Quote this message in a reply
03-04-2018, 04:41 PM
Post: #20
RE: Misfiring on cylinders 1-3.
You dont need to buy mhd to check codes.
Install the app and you can run the scan for free.

There are plenty cables for sale on gumtree and bidorbuy


Current:
2010 e92 335i Rennzport Tuned
2007 Golf 5 GTI DSG

EX Rides: 1991 e30 318i Vert, 1996 Jetta VR6 EXEC, 2002 Mini Cooper S, 2005 e46 320i Individual, 2007 E90 325i Msport, 1990 E30 318i, 1996 Golf 1, 2005 E82 130i Msport, 2011 E90 LCi 330d Msport, 1998 e36 323i motorsport, 2004 E46 M3 Vert, 2010 Audi A4 2.0T, 1998 E36 323i Motorsport
Find all posts by this user
Like Post Quote this message in a reply
Post Reply 




User(s) browsing this thread:
1 Guest(s)

Return to TopReturn to Content