Unfortunately we do not accept new members for free, Now Registration cost 30€, if you are interesting Send Email to [email protected]

N47 DPF backpressure sensor problem
21-03-2022, 20:09 PM,
Post: #1
XZBMW  N47 DPF backpressure sensor problem
Hi!
I have a strange problem with E84 N47. Backpressure sensor shows 20mbar when engine is off, and 23-25mbar when idling. DPF was just cleaned in specialised workshop, backpressure sensors is brand new OEM (also tried Hella and other OEM but used).
Because of that DPF is regenrating too frequently or sometimes it will throw 480A and 481A code and won't renegenrate until I clear the codes but filter is not clogged. 
Anyone had something similar?
Quote this message in a reply
21-03-2022, 20:27 PM,
Post: #2
RE: N47 DPF backpressure sensor problem
Is dpf still ok? i suspect your DPF is clogged.
Quote this message in a reply
21-03-2022, 20:57 PM,
Post: #3
RE: N47 DPF backpressure sensor problem
It's clean. I Can remove it and it still shows 20mbar when engine is off. Shouldn't it be 0?
Quote this message in a reply
21-03-2022, 21:02 PM,
Post: #4
RE: N47 DPF backpressure sensor problem
Have you checked what pressure you read with pressure tube disconnected? If OK - then tube/DPF is clogged. If not - then something electrical.
Quote this message in a reply
[+] 1 user says Thank You to Node for this post
21-03-2022, 21:49 PM, (This post was last modified: 21-03-2022, 21:50 PM by diagso.)
Post: #5
RE: N47 DPF backpressure sensor problem
Do you have a tune on DDE ? For my adjusting EGR valve solved the issue. I assumed that DPF is not liking the tune.

I was having same issues. First DPF went for a wash, still simmiliar errors. Replacement of various backpressure sensors. Same story.
Quote this message in a reply
[+] 1 user says Thank You to diagso for this post
21-03-2022, 21:59 PM, (This post was last modified: 21-03-2022, 21:59 PM by Krysiaman.)
Post: #6
RE: N47 DPF backpressure sensor problem
(21-03-2022, 21:02 PM)Node Wrote:  Have you checked what pressure you read with pressure tube disconnected? If OK - then tube/DPF is clogged. If not - then something electrical.

I will check that tomorrow.

(21-03-2022, 21:49 PM)diagso Wrote:  Do you have a tune on DDE ? For my adjusting EGR valve solved the issue. I assumed that DPF is not liking the tune.

I was having same issues. First DPF went for a wash, still simmiliar errors. Replacement of various backpressure sensors. Same story.

What do You mean by adjusting EGR?

Car is totally stock
Quote this message in a reply
22-03-2022, 06:30 AM,
Post: #7
RE: N47 DPF backpressure sensor problem
If you disconnect hose from sensor is the reading still 20mbar? What is the I-level of the car?
Quote this message in a reply
[+] 1 user says Thank You to unicoil for this post
22-03-2022, 06:33 AM,
Post: #8
RE: N47 DPF backpressure sensor problem
Vehicle management -> Troubleshooting -> Function Structure, next find "exhaust gas pressure sensor"
In ABL choos Functional check, and compare pressure to ambient pressure.
Many times i did have exhaust backpressure sensor that shows 1040 hpa, compared to atmospheric sensor showing about 1000 hpa. Permissible difference is 20 hpa.
Quote this message in a reply
[+] 1 user says Thank You to cursor for this post
22-03-2022, 08:33 AM,
Post: #9
RE: N47 DPF backpressure sensor problem
(22-03-2022, 06:33 AM)cursor Wrote:  Vehicle management -> Troubleshooting -> Function Structure, next find "exhaust gas pressure sensor"
In ABL choos Functional check, and compare pressure to ambient pressure.
Many times i did have exhaust backpressure sensor that shows 1040 hpa, compared to atmospheric sensor showing about 1000 hpa. Permissible difference is 20 hpa.

I tried now with another sensor. Now it shows -15mbar when engine is off or when hose is disconnected. 

In ABL i have: 
Atmospheric pressure: 1029 mbar 
Charge pressure: 1059 mbar
Exhaust backpressure: 1014 mbar 

Can it be charge pressure sensor?
Quote this message in a reply
22-03-2022, 10:34 AM,
Post: #10
RE: N47 DPF backpressure sensor problem
When exhaust backpressure sensor shows negativ pressure then in my experience this is due to faulty backpressure sensor. It is very common to go bad like this on backpressure sensors, I have changed with that kind a fault tens of sensors, after that were pressure readings OK. I recomend to use only OE senors.

What is the value of the sensor with a new OE sensor and hose from the sensor disconnected?
Reputation: +1 - al70 [+1]
Quote this message in a reply
[+] 1 user says Thank You to unicoil for this post


Possibly Related Threads…
Thread Author Replies Views Last Post
  Bmw G31 retrofit Mgu id7 atm problem intranet 20 2,542 26-04-2024, 08:06 AM
Last Post: smilo
XZBMW NBT EVO Connected Drive problem after update I-Level SkeYT 47 4,842 22-04-2024, 11:44 AM
Last Post: kwat
  BMW E60 coding problem GarageX 8 381 02-04-2024, 10:07 AM
Last Post: GarageX
XZBMW Bmw 5,f10 radio problem RobertRexhaj 3 178 28-03-2024, 18:47 PM
Last Post: Unspec
  ISTA launcher problem Red_bean_bun 1 292 26-03-2024, 05:11 AM
Last Post: 2013m5
  Dme Cas synchronization Problem donjuan020 3 283 25-03-2024, 21:55 PM
Last Post: BmwMerc
  BMW e39 530d 2001 problem after MAF change boweld11 3 178 24-03-2024, 22:44 PM
Last Post: SkeYT
XZBMW Entrynav2 Maps Problem Chillmeister 3 386 24-03-2024, 17:18 PM
Last Post: Chillmeister
  For anyone having problem with ICOM NEXT FW update via ISTA+. ImmBoo 16 4,493 24-03-2024, 11:29 AM
Last Post: Twointje
  Battery lead positive underfloor problem da.2022 10 344 24-03-2024, 09:38 AM
Last Post: pupu144

Forum Jump:


Users browsing this thread:
1 Guest(s)

Return to TopReturn to Content