[bambamBMW]

Hi,

I know there are a few in here that have had their fair share of issues with Dpf. I am nearly at the point of giving up on this and selling the car.


I have a 330d e91 2006. The car has recently developed the yellow Dpf fault 00480a and am experiencing a loss in performance - not really limp mode but acceleration is definitely not what it was. I have Carly but I cannot regenerate as Carly says there are faults which prevent regeneration request.

There were a few faults with the DDE that i have fixed and also both thermostats were replaced.

glow plug errors on 4 plugs
Glow plug module

All plugs were replaced and also the module. All these faults are now gone but I am left with the fault 00420 (or 4020): Exhaust gas temperature sensor before particle filter, signal

I've searched loads of forums on answers, but nothing seems to pinpoint error 4020 on Carly, and I don't know what else I can do to fix this. Don't want to go and buy other sensors unnecessarily, especially as they seem to be reading right.

I thought this sensor was the #1 on real oem as below.

https://www.flickr.com/photos/77837349@N05/51189052041

This sensor I changed, but the fault remains. I downloaded the fault live data (freeze frame) from Carly. I did this after the run, just to check to see if there was any more info on the fault 4020. There wasn't much to shed light on whats wrong.

https://www.flickr.com/photos/77837349@N05/51189056441

engine speed 661 rpm
coolant temperature 30c
rail pressure is 385 bar
injection quantity 8mg / stroke
air mass per cylinder 428 mg / stroke
boost pressure is 1024 mbar
exhaust gas temperature upstream of oxidation catalytic converter 89c
battery voltage 14v
intake air temperature 17c
voltage of exhaust gas temperature sensor in front of particle filter 4980mV

Here I took some readings of the temps on a 30 minute trip from cold to motorway driving. The temperatures seem good enough to perform a regen (I know, the oil is low and some Castrol on its way from Opie)

https://www.flickr.com/photos/77837349@N05/51189056451
https://www.flickr.com/photos/77837349@N05/51189272868
https://www.flickr.com/photos/77837349@N05/51189056446
https://www.flickr.com/photos/77837349@N05/51188350632

Would the 4020 error be in relation to temps or due to back pressure? I was thinking of going down the route of making a small cut in the rubber hose to the pressure sensor to fool the system into regenerating?

Appreciate any help here!

[Andystobbs]

You don't seem to have thought this through particularly well. Cutting the hose will lower the perceived back pressure and make the soot load appear lower.

EGT is a critical input for managing the regen. If you changed the correct sensor and it still has the same fault you need to look at wiring harness between it and the ECU - unless you have two defective sensors which is very unlikely.

[bambamBMW]

Originally Posted by Andystobbs

You don't seem to have thought this through particularly well. Cutting the hose will lower the perceived back pressure and make the soot load appear lower.

EGT is a critical input for managing the regen. If you changed the correct sensor and it still has the same fault you need to look at wiring harness between it and the ECU - unless you have two defective sensors which is very unlikely.

I wasnt suggesting this as a solution, just a temporary measure to get the dpf to a state where it would be possible to regen and clear the partial blockage.
I would have cut a small slit in the tube and then replace the tube once the dpf is clear. As you can see from the screenshots of the temps they do not appear completely erroneous such as in previous obviously faulty sensor cases (sensor reading in under 100 deg c in motorway driving).

I want to be able to do the regen without doing this ideally.

I don't know what the 4020 error is referring to though - I have read this error code can also mean a back pressure error.

[mt10argyll]

One thing for sure, your car won't regen with some particulate fault codes.

I was out with my son in his 2006 330d out for a run recently, his warning light had appeared on the dash, he only does short runs, which as we know is no good for diesel cars.

To get it to regen I was constantly deleting the fault codes after they kept reappearing, suddenly after about 20 mins, the car started to regen.
I must have cleared the codes at least 20 to 30 times when suddenly it happily kicked in, the soot could be seen lowering all the time.

I was using an Autel system but other types of readers will do

We had half a tank of fuel and only went about 50 to 60 MPH, no need to rag it.

[bambamBMW]

Originally Posted by mt10argyll

One thing for sure, your car won't regen with some particulate fault codes.

I was out with my son in his 2006 330d out for a run recently, his warning light had appeared on the dash, he only does short runs, which as we know is no good for diesel cars.

To get it to regen I was constantly deleting the fault codes after they kept reappearing, suddenly after about 20 mins, the car started to regen.
I must have cleared the codes at least 20 to 30 times when suddenly it happily kicked in, the soot could be seen lowering all the time.

I was using an Autel system but other types of readers will do

We had half a tank of fuel and only went about 50 to 60 MPH, no need to rag it.

What codes were coming up for your son? Were they DDE (exhaust) codes?

Problem with mine is I have a DDE code and the car won't regen with those codes present. I have tried deleting codes whilst driving but it hasn't made a difference so far. Just need to locate the fault with the sensor I guess.

[mt10argyll]

I think the codes were 480A , 481A meaning the dpf is full

[rasa bmw]

whatb are your coolant temps after a good 20 min drive,,they have to be at elast 75deg but should get above 90deg

[nick46]

Originally Posted by rasa bmw

whatb are your coolant temps after a good 20 min drive,,they have to be at elast 75deg but should get above 90deg

His coolant temperature was 90.75°C from looking at the pictures he posted of screen shots from Carly.

[Daviebrown]

When using DIS the fault is badly described as an exhaust gas temperature sensor when it should read exhaust gas pressure sensor, you need to look at your backpressure readings then maybe change the square sensor with the rubber hose connected to it.

[bambamBMW]

https://flic.kr/p/2m1ck8B
4020 has several faults linked to it

[mjn77]

How many miles on your DPF?

[bambamBMW]

Originally Posted by mjn77

How many miles on your DPF?

158k

[bambamBMW]

Just thought I'd post the resolution to this fault for anyone with the same 4020 error.

The fault was with the second temperature sensor (just before the pressure sensor hose) number 8 in picture. Confusing as the error description is 'exhaust gas temperature sensor before particle filter, signal'
Making you think it was the first temp sensor on the Dpf.

https://www.flickr.com/photos/778373...7719221364291/

Car now has 0 engine errors.

Just been for a regen run with carly running and the regeneration became active almost immediately. Did a 40 minunte run down the A3 and Soot mass went from 79g to 4g! with 8g of ash.


Car felt much better afterwards, much more responsive.

[mjn77]

Originally Posted by bambamBMW

158k

It's probably close to end of life. I got 162k out of mine before it needed a clean.

[bambamBMW]

Originally Posted by mjn77

It's probably close to end of life. I got 162k out of mine before it needed a clean.

Yeah probably. The car is going to have to go anyway I think. London and diesels won't mix for much longer.

I think I might start looking at X5M's or a Range Rover 4.4 while they are still allowed to exist...

[mjn77]

Originally Posted by bambamBMW

Yeah probably. The car is going to have to go anyway I think. London and diesels won't mix for much longer.

I think I might start looking at X5M's or a Range Rover 4.4 while they are still allowed to exist...

The London ULEZ was the only reason i got rid of my very well specced 335d. Replaced it with an E90 M3 ROFL!!

I now have no ULEZ charge.

[bambamBMW]

Originally Posted by mjn77

The London ULEZ was the only reason i got rid of my very well specced 335d. Replaced it with an E90 M3 ROFL!!

I now have no ULEZ charge.

Exactly. Good choice. I believe anything Petrol Euro6 (2006 and later) is exempt.

All fun and games till they block your road off with a bunch of LTN barriers.

[mjn77]

Petrol is EU4 and diesel is EU6.