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Dpf problems x5 sd /35d e70 high back pressure
Posted: Wed Jan 07, 2026 5:51 pm
by Leslie
After a few days of short run and idling to clear snow I have high dpf back pressure on my x5sd m57 engine , The dpf back pressure was 55 mbar but after a 40 mile run at low speed but highish revs 2500 rpm (single carriageway that actually increased to 75 mbar .
I added millers Dpf regeneration cleaner to a half tank of fuel and went out for 30 miles on a dual carriageway at 70 mph constant and it has now dropped to 35 mbar but it should be less than 10 mbar so I think its still too high for a regen to start.

I did request one but it hasn't happened and I can see anywhere on my Foxwell nt 530 to view soot/ash volume unfortunately.
I had codes for 480A and 481A (particulate filter system and now 426A boost pressure control low pressure stage control deviation and 4D00 exhaust back pressure sensor (back pressure is too high )
I've also lost what seems like 100 hp

, very noticeable when you floor it so its in limp mode , it does drive fine at lower speeds but the Dpf is strangling it above 60 mph .
I did have this before after similar driving and the dpf cleaner got it down to 20 mbar but I suspect the dpf either is blocked with ash etc and may need replaced , anybody had an success cleaning one with a tank based cleaner and removing these is a mountain of work for cleaning and no guarantee of success if its melted inside etc. I know my local mechanic would not be able to do this due to ill health .
Dpf problems x5 sd /35d e70 high back pressure
Posted: Wed Jan 07, 2026 6:41 pm
by X5Sport
All I can find in the manual is this (Note - those codes will prevent a regen as the DDE locks the function out until the codes are sorted.)
Diesel particle filter service instructions
Complaint:
The customer complains about the Check Control message "Diesel particle filter malfunction".
The following fault codes are saved (one or more):
480A / 245700 (from F01) DDE: Diesel particle filter - filter is heavily contaminated. (exhaust backpressure is too high)
481A / 245800 (from F01) DDE: Diesel particle filter - filter is heavily contaminated. (exhaust backpressure is above maximum)
Cause:
The diesel particulate filter is overloaded. Regeneration of the diesel particle filter is being prevented by the DDE.
The following cases can arise:
On the 325d and 525d with engine M57TUE:
unfavourable DDE software. The following integration levels are required:
325D E89x-09-12-512 or higher
525D E60x-09-12-512 or higher
The diesel particle filter is clogged due the recent driving profile.
Frequent short-distance drives and urban driving cause the diesel particle filter regeneration function to work less efficiently. Longer, extended and insufficient regeneration triggers the fault entry 480A / 245700 (from F01). As soon as the fault is saved, regeneration is then no longer possible. This function is inhibited.
If the diesel particulate filter does not continuously regenerate itself and the exhaust gas pressure continues to rise, the fault code 481A / 245800 (as of F01) is also entered. The Check Control message "Diesel particle filter malfunction" appears on screen.
Engine fault
other additional engine faults are also present
Measure:
On the 325d and the 525d M57TUE:
Ensure that the vehicle is programmed with the following integration levels, otherwise update the integration level:
325D E89x-09-12-512 or higher
525D E60x-09-12-512 or higher
Perform a vehicle test and all relevant test modules. In the DDE, no relevant fault codes are allowed to be saved to memory, with the exception of 480A / 245700 (from F01) and 481A / 245800 (from F01). First correct the existing faults.
Relevant fault codes are faults from the following areas:
Charge air system
Exhaust emission system
Sensors (exhaust gas pressure sensor, exhaust-gas temperature sensor)
NOTE: it is possible that the customer may bring the vehicle to the workshop due to the Check Control message, but the system has in the meantime already regenerated itself (e.g.: through an extended motorway journey). The customer is now aware of this process occurring. Check if the fault status is set to "Currently not present", then delete the fault memory.
Distance driven since last successful regeneration
Carry out the test modules for fault codes 480A / 245700 (as of F01) and 481A / 245800 (as of F01), carry out the exhaust gas pressure test and keep a record of the exhaust gas pressure values.
Request regeneration using the service function.
NOTE: Regeneration is blocked by fault codes 480A / 245700 (from F01) and 481A / 245800 (from F01). Regeneration does not take place until the faults have been rectified by an extended regeneration drive (refer to chapter on regeneration)
Carry out a regeneration drive
Once faults 480A / 245700 (from F01) and 481A / 245800 (from F01) have been saved, drive the vehicle for about 45 minutes at a constant speed. In addition, switch on electrical consumers to keep the exhaust-gas temperature between 280-350°C. That enables continuous regeneration to take place, the exhaust backpressure drops, the faults are remedied and the following status message is issued: "currently not present". Now, normal regeneration takes place automatically.
Establish the distance driven since the last regeneration and check to find out if periodic regeneration has taken place. This status message is used to confirm successful regeneration.
Carry out another exhaust backpressure test with the diagnosis system. The exhaust backpressure must match the nominal values. If it does not, carry out the following checks:
check the charge air system
Check air intake hose for leaks
Check charge air hoses for leaks
perform air mass system test
carry out function check of swirl flaps and exhaust-gas recirculation valve
Check exhaust emission system:
Check exhaust backpressure hose to diesel particulate filter for leaks and damage
Check exhaust sensors: Check the plausibility of the temperature sensors, check the exhaust gas pressure sensor
Regeneration
There are two kinds of regeneration:
Continuous regeneration:
This form of regeneration takes place during normal driving. At exhaust-gas temperatures of between 280-350°C, continuous regeneration takes place in the form of a slow oxidation process. The soot particles cannot be incinerated until the exhaust gases reach the required temperature.
Periodic regeneration:
Periodic regeneration is performed automatically by the DDE after no later than 1000 km (600 miles). On vehicles with many short-distance drives, periodic regeneration already starts taking place after just 400 - 800 km (250 - 500 miles).
For regeneration, the intake air is reduced by the throttle valve. One or two post-injections are performed. This increases the exhaust-gas temperature to about 600 °C. The soot is incinerated with the residual oxygen.
The periodic regeneration is performed at all speeds. The most efficient method is regeneration at a constant speed in excess of 60 km/h (38 mph) over a period of 20-30 minutes.
The DDE calculates the time for periodic regeneration from the following values:
average distance travelled
average driving speed
temperature in the diesel particle filter
values from the exhaust gas pressure sensor
The last successful regeneration can be read out by the diagnosis system
The following conditions must be fulfilled for a regeneration:
The coolant temperature must be in excess of 75 °C
the exhaust-gas temperature before the diesel particle filter must be greater than 240 °C
there must be enough fuel (fuel reserve indicator light is not lit up). Whenever the reserve lamp lights up, the regeneration process is suspended.
no fault codes from the air mass system, exhaust emission system and sensors must be saved in the DDE
The fault codes 480A / 245700 (from F01) and 481A / 245800 (from F01) must display the status "currently not present"
Constant driving speed above about 60 km/h (approx. 38 mph). The optimum speed is about 100 km/h (approx. 60 mph).
Dpf problems x5 sd /35d e70 high back pressure
Posted: Wed Jan 07, 2026 7:17 pm
by Leslie
That's x5sport

that's interesting , I think my issue is I'm not getting periodic regens anymore only continuous regeneration due to high temps which is just keeping things ticking over and no more if I do one good high rpm run a week , this hasn't been happening so rigidly as before and its showing.
I think this has been an issue since my injectors failed so its possible going by that I have air leaks at the inlet manifold as I thought id be back in again so I never changed the seal despite buying them, they looked ok though tbh . I need to check last noted regen if I can find it .
Also coolant temp is now 80 to 82 which should be enough but less than I think 88 when the stats were changed which is more an issue in these colder conditions.
At the minute it looks like more dpf cleaner and pound the dual carriageway till the back pressure drops to a normal level if possible as these codes are stopping proper regens happening but maybe take the inlet back off , its too cold now and I don't fancy doing it again just yet outside

Dpf problems x5 sd /35d e70 high back pressure
Posted: Wed Jan 07, 2026 8:07 pm
by Leslie
5630 km ( 3500 miles) since last regen

but the one before that was a further 9000km (you can only see last 2) and its under microfilter on the foxwell nt 530 , I have found request regen in there so will give that a go in a few days see what happens
It seems proper regens stopped some time ago or maybe my once a week drive did enough to make them not quite needed who knows as I've had it 7 years now and no dpf issues till last year .
3500 miles is very close to the time injector 5 left the chat and it took at least 10 restarts to get to the garage to work at it ,with it cutting out every few 100 yards in the end but it doesn't appear to be working before that either unless that data is lost with battery disconnection ?
Dpf problems x5 sd /35d e70 high back pressure
Posted: Sat Jan 10, 2026 4:17 pm
by Leslie
Coolant temp is dropping below 75c while driving in cold weather so I guess new thermostats are needed before we csn progress.
I do have a throttle valve code as well but not sure if that would stop it regenning , I set regen to active and requested regen so far but made no difference , also found car was still programmmed for an agm battery despite having a lead acid this last 7 years of my ownership probably longer , so recoded that while I had the code reader on. It said the foxwell couldn't do this when I bought it bit it apeears to have worked, may only work on some models , no option for 100ah only 90 or 110 so set it to 90 ah.
Dpf problems x5 sd /35d e70 high back pressure
Posted: Sat Jan 10, 2026 4:56 pm
by X5Sport
The book says that air is restricted by the throttle calve during regen, and injection cycles increased. It might be the issue, but defo ‘stats need looking at if the temp is below requirement. Change them first would be my approach.
I use AGM as those are the ‘standard’, but like you I can’t set it exactly right as the Yuasa I use is different to the BMW rating. Carly doesn’t have a setting for that either.