[Bevan]

Hi all...changed my fuel filter today on my diesel e92 however the blocked fuel filter warning light still shows when first started and will eventually pop up while driving. Cleared all codes and still shows it coming on from time to time, has anyone else experienced the same problem as me? Is there a fix to resolve this? I mean I know the filter has been changed and it's fine (well I hope) but it's just irritating that's all.

Thanks.

[Sensible_]

Are you referring to the Diesel Particulate Filter (DPF) warning light?

If so, changing the fuel filter won't help. You'll need to go through the steps of a DPF regen and repair any issues preventing regeneration.

[bishbosh]

Correct, the particulate filter as part of the exhaust system, just behind the turbo. Nothing to do with the fuel filter which is underneath the passenger seat.

[Bevan]

Originally Posted by Sensible_

Are you referring to the Diesel Particulate Filter (DPF) warning light?

If so, changing the fuel filter won't help. You'll need to go through the steps of a DPF regen and repair any issues preventing regeneration.

Yes I am, well I think I am the half clogged filter symbol right?

Thanks for that, are we talking a big job? Could I do this on my own or would it take a specialist to do? Thanks.

Originally Posted by bishbosh

Correct, the particulate filter as part of the exhaust system, just behind the turbo. Nothing to do with the fuel filter which is underneath the passenger seat.

Thanks for your input on this, and here's me thinking just changing the fuel filter would resolve the problem
More work to do I guess...

[richard_tricky]

its usually something else. that will cause a particulate filter problem.

One of the most common causes is the engine not being able to get up to the required temperature (75c) due to the thermostats being stuck open and then the DPF wont regenerate,

there can be other reasons car will not regenerate however,

First you need to read the fault codes, get that done and come back here.

have a look at this post for some guidance

http://www.e90post.com/forums/showthread.php?t=1456927

[Sensible_]

Originally Posted by Bevan

Yes I am, well I think I am the half clogged filter symbol right?

Thanks for that, are we talking a big job? Could I do this on my own or would it take a specialist to do? Thanks.

Thanks for your input on this, and here's me thinking just changing the fuel filter would resolve the problem
More work to do I guess...

It's perfectly achievable by yourself.

As stated, start by seeing what your coolant temp is getting to on a a short drive. Use something like Carly or just the dash secret menu to monitor this. You should get up to around 88c pretty quickly.

If you just see 70s then you'll need to change the thermostats.

Make sure you have more than 10l of fuel in the tank aswell.

There are a few other conditions which need to be met aswell prior to a DPF regeneration. But start with what's already been stated. Once everything is met take the car for a long drive (and I mean long) on the motorway. Stay at a constant speed above 60kph. The ECU will take care of the rest.

You don't need any specialist help to regen the DPF. I've recovered very blocked DPF's by this method.

[bfleming]

First step here is to have your codes read to see what's causing the DPF error. I've seen them all over the years on various cars (luckily not my E90!). In general there will be little wrong with the DPF to begin with, but the conditions for it to regen aren't being met. Some causes:
Car not up to temperature. This was common on the M47 cars due to their thermostats (2 of them, main & EGR) going bad. The N47 is different so doesn't commonly have this issue.
DPF pressure sensor bad. The car needs to know how full the DPF is to request a regen, and if it can't read this due to a bad pressure sensor, it wount regen.
It's too full - it won't regen if it's too full, and this can lead to other issues like turbo seals going bang due to backpressure. I've had it happen once on a Focus. So keep driving with the warning light on at your peril.
To regen you need to be going over 2000rpm for a period of time, and all the other conditions need to be good (temp & pressure). Urban driving is a killer for DPF's.

Can you say whether or not you have a M47 or N47 engine, and what your driving environment is. Mileage & registration year will also help.

Lastly taking a DPF off the E90 is a straightforward task. Cleaning it is not as it shares a housing with the catalytic converter. They need to be cut apart, the DPF cleaned, then re-welded.

[matt_s]

Hi, some good advice with the above, tell us what codes you're getting, might help pinpoint the issue. Above all, fix what's causing the issue first, before even starting to look at the dpf. Don't go throwing money at it, the forum will give you lots of pointers and advice.

On my e90 I had the dpf cleaned in the car, using BG products (took it to somebody), i didn't need to remove/reweld the dpf - but that was the m57 engine. Haven't looked back in the last 20k miles...