DPF & Brick Acid Question

[Doo]

Was advised to clean the ash in my DPF with brick acid. I bought the necessary & am about to relieve the engine of the (stupid) DPF so who knows the formula?

Is it straight out of the bottle, 1 to 1 mix or 20 parts water to 1 part BA??? How long do I let it sit? Do I slosh it about? Then I imagine I backwash it out with high pressure wash. Do I use cold water, hot water or steaming hot (155 Celcius) water? Low or high pressure?

Sorry for all the questions, but in all my days as a mechanic, I have never dealt with this nonsense. But I love a challenge....

[Paul-R]

Don't use it neat! It's too strong and will attack the stainless steel. You might want to precede the acid with an alkali wash if it's oily.

This YouTube video has been posted on here before now but bears repeating.

[Doo]

I have removed it, split it and AFAICT it's immaculate! I have never seen anything so clean! The brickwork is a slight brown colour, but NOT a pick of soot or anything blocking the honeycombs.

I pulled off the pipe from the turbo compressor to the intercooler and it was gleaming! I mean, NO oil on it whatsoever. I expected a slight weep, but nothing! The feed from the compressor is also immaculate...

So Why is it telling me stuff's blocked (it actually stated Ash 100% ) so unless they store the ash in a wee bin, I'm at a loss as to what it's on about!?

[RichardW]

There's a pre determined life of the filter, according to the ECU - then it will flag risk of filter blocking all the time, and when you check it will say ash 100% and filter life remaining 0km. As long as the pressures are OK (say <10 mbar at idle and <40 or so 3000 rpm unloaded) then you can just tell it it's been replaced and it will go away happy.

[Doo]

There's a pre determined life of the filter, according to the ECU - then it will flag risk of filter blocking all the time, and when you check it will say ash 100% and filter life remaining 0km. As long as the pressures are OK (say <10 mbar at idle and <40 or so 3000 rpm unloaded) then you can just tell it it's been replaced and it will go away happy.

That's the thing, I have tried to tell it it's been done, but it want's a "key" which I assume is some sort of code speak. I'll give it a wash with the brick acid as per the video, but not convinced it is at all bad. I'll take before & after photo's. I have NO soot whatsoever, so don't need to be as thorough as the video.

Thank you for your time explaining this.

[Hell Razor5543]

I wonder if the DPF was properly cleaned in the past (before the car entered your ownership) but the ECU was not told it had been 'replaced'?

I have (on a couple of occasions) tried to perform a task with the Lexia which the required an 'authorisation code' before it could perform the task. I wonder if that is what you mean by a 'key'?

[Doo]

Upon looking into the top of the DPF, there is a little soot. But the other end is free of soot. But looking in the sunlight, I think perhaps the ash is present (was expecting it to be a different colour if I'm honest ).

Ahh well, to work

[GiveMeABreak]

There's a pre determined life of the filter, according to the ECU - then it will flag risk of filter blocking all the time, and when you check it will say ash 100% and filter life remaining 0km. As long as the pressures are OK (say <10 mbar at idle and <40 or so 3000 rpm unloaded) then you can just tell it it's been replaced and it will go away happy.

That's the thing, I have tried to tell it it's been done, but it want's a "key" which I assume is some sort of code speak. I'll give it a wash with the brick acid as per the video, but not convinced it is at all bad. I'll take before & after photo's. I have NO soot whatsoever, so don't need to be as thorough as the video.

Thank you for your time explaining this.

Don't forget that you can't see the Cerine deposits that are miniscule and are embedded within the filter walls.

What software are you using? Diagbox or Lexia as regards to a 'key'?

[Paul-R]

You wouldn't necessarily see soot in the DPF, especially if it's recently regenerated. What collects is the unburnable ash, cerine and iron products. The iron is what gives it the orangey red colour.

[RichardW]

I've done it once and wasn't asked for a key / code, but different ages / Diagbox versions may be different. Wheeler will probably know what it is if he drops in....

[GiveMeABreak]

There should be no codes required whatsoever in Diagbox for this operation, nor in Lexia, unless your referring to a code it is asking in Diagbox for connection to the servers (like a technician log in and password)...

You only need to log into Diagbox for certain configuration options on later versions higher than 7.58.

[Hell Razor5543]

For some tasks a Lexia may ask for an authorisation code (for want of a better term). Try 03114, and see if that works.

[Jay-Bruce]

For some tasks a Lexia may ask for an authorisation code (for want of a better term). Try 03114, and see if that works.

That could prove invaluable and should be stickied somewhere.

[Paul-R]

For some tasks a Lexia may ask for an authorisation code (for want of a better term). Try 03114, and see if that works.

That could prove invaluable and should be stickied somewhere.

Indeed, I have a small Post-It note with that number written on stuck to my Diagbox laptop.

[wheeler]

I’ve never been asked for a code when doing any DPF or fluid/tank replacement. Can you post a screenshot of what it’s asking you?
The 03114 is normally only asked for when changing any configuration of the BSI.