w.ashcroft

Hello,
A week or so ago I was driving along when an error popped up on the iDrive screen:

Particle Filter - Possible to continue journey. Possible reduction in engine power. Have the problem checked by your BMW Service.

Checking with INPA I had a few DPF related error codes and some glow plug failures. Further investigation with the help of this forum led me to replacing all the glow plugs, glow plug controller and both thermostats because the engine was also running cool (70 degrees). I suspect the thermostats had prevented regenerations eventually raising the alarm.

Now following all this work, I expected to be able to reset the errors, force a regeneration via the service functions in DIS and let it regenerate but so far it has not. I have driven 100's of miles in optimum conditions, with the laptop open running DIS monitoring the status of DPF regeneration. Exhaust temperature is 350-400 degrees, coolant temperature is 90 degrees, regeneration is enabled, requested in DDE but never changes from "not active".

The car is not in limp mode and if anything there is only a slight loss of performance at the top end.

When starting the car, there are no errors in iDrive, but after 10 minutes of driving the Particle Filter error returns without fail. My INPA error codes are 4030, 452A, 480A, 481A, 4D00 and upon clearing them a couple return immediately.

Any idea what I am missing to get a regeneration?

Is it true it won't ever try to regenerate whilst the error is showing in iDrive, and what changes for it to flash up 10 minutes into any journey?

Thanks in advance for any help.

ripley

You might be surprised how much performance is missing when the car is like this - I was with mine.

Some people have forced regen by continually clearing the codes while driving (may need a buddy).

Others fool the back pressure sensor with (I think) partial disconnection.

Myself, I have had the DPF cleaned off the car once (hassle to remove) and on the car with Liqui Moly (very easy but had to fabricate a sprayer). Both worked very well.

w.ashcroft

I can try continually clearing the errors during a motorway drive. Is that clearing the errors every few seconds or only everytime the code returns? I could setup the laptop to automatically press F2 in INPA every few seconds.

I've also learned tonight that some people have fooled the backpressure sensor by replacing the hose with one that has a small slit/hole in it - now the car thinks there is less pressure buildup, assumes it isn't heavily blocked and allows regenerations. Seems crazy, but worth a shot?

ripley

I would start with the first option since it is less invasive.

Do you have any backpressure or soot mass readings?

w.ashcroft

Constantly clearing the errors didn't work this morning, I'll give it another try before looking at bypassing the sensor - is it located in the engine bay or under the car?

Idle: 89 mbar
Max: 35 mbar

2000rpm: 274 mbar
Max: 75 mbar

Cutoff: 564 mbar
Max: 200 mbar

ripley

Engine bay - and it can get pretty tight.

Also you need to have enough fuel in the tank - not sure what the limit is so I just fill up.

w.ashcroft

Thanks, looks like this is it (X2389). I will let you know how it goes!

w.ashcroft

This worked (to reduce backpressure readings)!

Although the unit still hasn't regenerated probably because after clearing the fault codes, they haven't returned with the now low backpressure. Additionally, it isn't accepting a forced regeneration via DIS service functions and stays at "Regeneration not requested". Even with the hose returned to normal, backpressure is back up but still no DPF blocked related fault codes.

However, I am still left with the following single fault code which still wont clear:

4030

Which seems to mean one of these things depending on DDE version, although both sensors are reporting accurately.

EGT (exhaust gas temperature) Before Cat - Open Circuit or Short Circuit to B+
Exhaust Backpressure Sensor Before Particulate Filter - Signal

ripley

Hmm.

How many metres since last regen?

w.ashcroft

480A and 481A did return eventually with the original hose back on the sensor, I just need to figure out this 4030 error to be error-free (with my pressure reducing hose to trick it)...