[newbos]

Hi all

I have searched on the forum, but I'm not sure what to look for . Basically On my I drive it is showing a dpf fault; the car is drivable but I have reduced power. I got the car scanned and it's showing all my glow plugs are at fault, but yet my car ticks over and starts fine. They cleared the faults but my dpf fault keeps appearing. So are my glow plugs and relay faulty as well as my dpf?

Thanks

[makkan00]

I have been told if it shows more than 2 glow plugs, then glow plugs controller could be faulty.

[newbos]

I am assuming that, but with the dpf fault showing wouldn't that cause a build up of soot on all plugs? Hence all plugs showing fault.

[tmarshall57]

I may be wrong but I think that there is a link between inoperable glow plugs (say - due to faulty controller) and the DPFs ability to regenerate.

Without more accurate descriptions of the codes it is difficult to judge.

[newbos]

My knowledge is if a glow plug fault shows let alone all of them the dpf will not regen. So what if I change the controller and clean the dpf out, will this solve my issue?

[Sensible_]

Originally Posted by newbos

My knowledge is if a glow plug fault shows let alone all of them the dpf will not regen. So what if I change the controller and clean the dpf out, will this solve my issue?

Correct. Glow plug faults will prevent dpf regens.

This will result in the initial code 480A and then a further one when completely clogged.

However, you should check 1st to make sure its not a glow plug controller fault. Changing the controller won't help if one of your plugs are screwed though. I agree with makkan regarding if more than 2 are out it'll be a controller fault. I think ISTA D might be able to interrogate the glow plug controller re voltage, not 100% tho.

If you do change the plugs, I'd change them all and then the clear the dpf fault code. I personally regen the dpf by going for a drive for at least 20mins in a suitable gear and speed, on a flat road. For most n47 engines I use 4th at 60-70mph.

You should see the regens via the mpg swing.

If this isn't working you should use ISTA D and force regen the dpf. This way also works well.

[newbos]

Thanks for this guys. So If I change both my plugs and controller my dpf issue could go away? Will I get full power back?

[makkan00]

Originally Posted by newbos

Thanks for this guys. So If I change both my plugs and controller my dpf issue could go away? Will I get full power back?

What others said.

If you do not have ISTA D, then first line of protocol would be
- Change the glow plug controller.
- Erase the error.

If there is any problem with glow plug, it will return and in that case change the relevant glow plug.


Once this is resolved, the dpf will regenerate and you should have full power.

Other method is force dpf regeneration which is temporary solution as glow plug issue with recreate the same scenario again at later stage.

Do you feel comfortable sharing your current mileage?

[newbos]

Thanks, no problem with saying it's a high miler. It's just at 110thou, but you wouldn't know. I only run it on v power diesel and when I took the egr off it was spotless.

[Sensible_]

You should definitely remove and inspect the controller. Is it an N57 engine? It could be a dodgy connection.

I've changed the controller on a couple of N47's and it wasn't a major head ache. Where as the plugs are obviously a manifold off job.

They are around £100 from the dealer I think. Probably cheaper off eBay.

[newbos]

Yes it's a n57 engine

[old grey steve]

You'd normally see a series of gods to substantiate that the controller was also at fault but all 6 playing up is normally a bit if a giveaway.

Regarding the power issue and DPF glows will play a part but don't be surprised to discover that you lack of power issues lies elsewhere as various codes can and I've seen it where cars have been diagnosed elsewhere give you a bum steer.

Look at the pressure converter under the inlet manifold as one example, we've done shed loads of them and changing this one item can make a huge difference this will have a bearing elsewhere.

But re the DPF glows as stated when operating as required will allow a re gen process to take place. Mileage on these cars can have a bearing look at the manual from memory it's system somewhere in there they the DPF has a usually mileage expectancy if 100,000 miles, which a lot if them seem to go past or seem to not meet.

I've git a 109500 mike 325d in Wednesday with a failure and just before the end if July replaced a knackered DPF on a 84000 mile 335d which had to me at least been driven if economy net result of saving a few pence on fuel was a £1300+ DPF bill.

[tmarshall57]

Other factors that will prevent a DPF regen are faulty thermostats causing the engine to fail to reach normal operating temperature of 90-92 degrees. Test the coolant temperature using the hidden menu.

Replacing the EGR and main thermostats is the usual cure if you are only reaching low 80s after a 20 minute run. Obviously first base is the glow plug issue. Mines done 175k miles. One glow plug error at 80k. Glowplug replaced. DPF showing back pressures well within tolerance - proably due to 90% of mileage travelled at night on motorways.

[newbos]

I'm being thick I think, but where is the controller situated? Is it easy to get to? Or is it under manifold?

Thanks

[tmarshall57]

On mine it is on RHS of engine.

See this

http://workshop-manuals.com/bmw/3_se...(m57tu_m57t2)/

[Sensible_]

For N57 see this previous thread for pictures:

http://www.e90post.com/forums/showthread.php?t=794938

[mammoo6]

Definitely sounds like the glow unit... Had the exact same fault... Although not impossible highly unlikely that all 6 will go at the one time.

Done it about 8 months ago and it's now brought the dpf issue up again... Shoved it on the computer and temps getting to 81 max on motorway so in the garage covered under warranty �

I took a couple of photos whilst replacing the unit... I'll try and find them... Not hard but quite fidly and you need to remove quite a bit for access

Matthew

[newbos]

Cheers Matt

[newbos]

Can you do this without taking manifold off? or do you need hands of a 2 yr old to get to it?

[mammoo6]

Doubt hands of a 2 year old would even get to it to be honest

Need to take the manifold and disconnect a few of the coolant pipes... Well I did anyway to save any hassle.
On my road home just now mate so I'll have a look on the HardDrive when I get in for the photos

[newbos]

Cheers mate, appreciated!! �

[KM79]

Originally Posted by newbos

Can you do this without taking manifold off? or do you need hands of a 2 yr old to get to it?

Yes you can but it's 1000 times easier if you can get underneath the car to do it.Its only two bolts and two connectors.