[Theador]

I was about to have the DPF removed on my 320D e91 MY 2005 ahead of putting an evolve map on my car, but when I spoke to the garage who normally service my car, they said they'd heard a few stories about BMW's having turbo failure shortly after DPF removal. They just said it seemed to be a little too frequent to be a coincidence.

He explained it as oil getting in the engine, blocking something and then the car accelerating the engine and draining all the oil through the turbo, or something like that.

Has anyone got any knowledge of this?

[dixy2k]

The DPF is not part of the exhaust-turbo-engine-intake cycle.

[DieselRacer]

Unless because of less back pressure you get boost creep which occurs in VW TDI's that are tuned with straight pipes, when this happens the tune went wrong and it can be fixed with software, in a VW diesel at least...

[Yozh]

Ecotune apparently has designed protection from overboost situations in their tune with consideration of DPF removal.

[Theador]

Yeah I think that's what he was referring to.

Is that known as an issue on a 2005 E91 320D? I don't know if evolve maps have over boost protection or not.

Originally Posted by DieselRacer

Unless because of less back pressure you get boost creep which occurs in VW TDI's that are tuned with straight pipes, when this happens the tune went wrong and it can be fixed with software, in a VW diesel at least...

[Theador]

I suppose the Bigger question is, is it worth whipping it out? There's no problem with the DPF at the moment, I'm only removing it to try and get a couple more Horses out of the car.

[Bicax]

Some people remove the DPF as a preventive measure, seeing how expensive it is to replace when it does fail.

I'm not saying that you should do it, but just that if you are thinking of doing it anyways it might not be a bad idea to go ahead before your DPF fails.

[Theador]

If it fails, is it then just a case of removing it, or does it kill other things too on its way out? I'm not sure exactly how it works, I thought it was just another filter.

So it sounds like the issue with blown turbos as a result of removing DPF's isn't actually an issue?

[floydarogers]

Originally Posted by Theador

So it sounds like the issue with blown turbos as a result of removing DPF's isn't actually an issue?

No, it's definitely an issue - check the threads on removing the DPF for 335d cars - removing the DPF reduces the backpressure and can cause the turbos to over-speed.

Re-read the first three responses.

[DieselRacer]

Boost creep is only a problem if it cant be tuned out, removing the DPF will allow the turbo to spool faster and a chance of boost creep unless it is written in the tune...