Not keen on first post being a fault code, but oh well...

This car is a mix work beast and family car...  it covers approx 4000 miles per month, predominantly on the open road/motorways. 

Only had it since July - it was serviced not long before purchase and again approx 2-3 months ago.  There have been no issues with it at all.

Was serviced again yesterday - and brake pads replaced, brake sensor also.  The service interval/warning was all then reset.Immediately afterwards car into limp mode - underpowered and showing code 452A (if i remember right) - either way it was basically saying the DPF is at the end of its natural life.

Now there have been no previous dpf exhaust issues.... the car has been running fine and is well maintained. At the amount of miles on motorway and occasionally enthusiastic driving the dpf should blast itself clean without problem...   seems to me this is some sensor glitch when the intervals/warning were reset from the brakes and service.

There was no way to reset/override the dpf issue and "limp mode" so car currently at exhaust specialist down the the road where they will poke deeper into dpf side of things...

Has anyone come across anything like this before?

Apologies for linking to another forum, but this seems to be similar problem:-

https://www.bimmerforums.co.uk/forum/f125/bmw-e91-320d-n47-dpf-fault-codes-4d4a-452a-t476610/

 

Normally you can get the DPF to regenerate by keeping revs at about 3000rpm (our son does it with his Toyota) does need a good blast with the engine at working temperature. The preset service intervals are probably at the bottom of the issue if they aren't reset correctly the DPF may be out of sinc.

Good Luck 

Dave

 

If it does it again, before it derates, load it down with people and luggage and make it chug up the steepest hill you can find to get the exhaust temps as high as possible.  Dont turn the key off until the lights go out or it will de rate.  If you do it right you'll see a cloud of black soot blow from the tailpipe and a rumbling sound as the DPF finally lights off.  You're trying to light a chimney fire, that's how a DPF works.

DPFs hate idling and stop and go traffic and light loads.  Get it out on the open road with a nice heavy load, find some hills, race it, whatever you have to do to get the exhaust hot.

Lockdown has had me backtracking into all my old car forums from over the years....

Dont want to be someone that just pops in when in need....

This problem well the main, initial part of it turned out to be a blue rag the mechanic had left in the airbox during the service.  He was incredibly apologetic and paid the resultant bill from the emergency garage I took it to.

The end of life dpf fault still persisted but there didnt seem to any issue and it was always on my "to sort" list as I had switched my main drive to another vehicle and the little M Sport was just fun car and occasional run around.