P1a58/006744

DPF light on. Went for a long ride Regen occured. Light went off then back on. Checked soot levels actual is low 2 and calculated 0. So not DPF. Checked and received the Nox regeneration code stored. I know this has something to do with the fix. Should I head to the dealer to get fixed under extended emissions warranty? I also plan to get a Malone tune in the next few weeks. Will the tune get rid of this fault altogether and forget the dealer, or should I head to dealer first?

The dealer has the discretion to turn down warrenty with any modifications. Id get the issue ironed out first under warrenty. Its always good to start with a good foundation anyway.

Yes that's what I was thinking. Very little info available on this fault. Will make an appointment with the dealer. Will post updates if any.

Did you find anything with this? I'm seeing the same code. I tried the nox regen option in VCDS but even after an hour of driving (and seeing the hex value it says indicates completion) I'm still seeing the DPF light and that code.

Yes I tried the same as you (DPF numbers are good). This code has something to do with the fix and the new NOX limits set. This fault code is a reserved type where the manufacturer can use and provide a specific description.Unfortunately the dealer is booked solid. Have an appointment in the second week of September. Will keep you posted. Although the dealer said it is on warranty if any of the emissions system is at fault.

I was able to get mine in next Wednesday. So I may be able to tell you before then.

So did you get any updates?

Their tech tried twice get the regen cycle to run. That didn't work. They've had a ticket open with the VW tech line since Wednesday but no resolution yet. Fortunately a loaner came in the night before so I've had something to drive.

I have my appointment for the 5th, lets see what their findings are. Thanks for the update.

I got a call today that it's ready to go. They ended up replacing the NOx filter.

Good to know. Will see if they do the same to mine tomorrow. Will keep you posted. Thanks for the quick update.

Well, that wasn't it. Or at least not all of it. I picked up the car this afternoon and ten minutes down the road, the light popped back on. So it's back at the dealership.

They are changing 2 glow plugs and the NOX sensor. They will only have the parts tomorrow. Will keep you posted if this will work or not.
Don't know if the glow plugs are related but no codes but some reading were at the limits apparently so they will change them since extended emission warranty applies.

Oh, hey. The DPF light is on again with the same code. Back to the dealer.

On the last one they forgot to do a regen cycle after replacing the NOX filter. So that why they said the light came on after I picked it up.

ziggy55 said:

They are changing 2 glow plugs and the NOX sensor. They will only have the parts tomorrow. Will keep you posted if this will work or not.
Don't know if the glow plugs are related but no codes but some reading were at the limits apparently so they will change them since extended emission warranty applies.

Click to expand...

Keep us up on this please. Im having a p13ce & p13do CEL

The dealer has been working with the VW tech line again on it. This time they’ve decided that the DPF needs to be replaced. It’s on back order with no ETA so it sounds like it could be a little while.

They've changed their minds. Now they're doing the NOX filter again.

I guess I forgot to come back and update this. The second NOX filter replacement ended up taking care of this one. At least for about another year until I sold the car.

Mr. Noggin, thanks for your response. I just now tested with Carly and got the following codes.


*** Freeze Frame Report ***
******
Motor Control --- Engine
(006744)
<FreezeFrameDataSet: 0x282591f00>
******
P2146
<FreezeFrameDataSet: 0x2826737a0>
******
P1240
<FreezeFrameDataSet: 0x282595a80>
******
P046C
<FreezeFrameDataSet: 0x2826687c0>

Just wanted to add my experience with the P1A58 (2011 Audi A3 TDI). After a couple times of being at the dealership for the P1A58 (which I too can't shake forcing a regen with the VCDS)... the last time the dealer had it (back in Jan 2023)... they finally decided they needed to replace the NOx converter (under warranty). I also had them replace the thermostat (out of pocket) since I noticed it was barely allowing the car to reach 87 degrees C. The TDS called this out, but for some reason Audi seemed to have missed it. But based on the TDS, a bad thermostat (ie an engine not hot enough) can create issue for NOx regen.

Anyway... new NOx, new thermostat... 6,000 miles later... P1A58 is back. It seems like this is can be a chronic issue... even after a new NOx.

Would likr to know if any of you have finally been able to get it fixed and have it last years thereafter without returning?

I have 3000 miles left on my emissions warranty... and if the prognosis is that I will always be dealing with this... I'll probably just have to sell the car after this last fix. I'd hate to do that. I love the car. If I can hang on to it for another 5 years/100K miles, I'd love to keep it. But all this DPF this and DPF that... makes me think these cars have a finite shelf life regardless of how well you take care of it... and a new DPF and/or NOx would basically "total" the car.

Thought?

I too have thought about selling my car but have decided if I can’t fix it I will gut the DPF and give it a time to let it know it has no DPF and keep it. The engines are good it is just the emission stuff that is bad. A tune will also up the power.

"Gut the DPF?"
I'm not familiar with this. Is this a common "solution"? I've heard of "DPF Delete" on diesel trucks, but I don't know if that's a thing people do for TDIs.

It means getting rid of the inner part of the DOF and leaving just the shell. Then getting a tune like Malone to tell the ECU that thee is no DPF.

Ok... I'm learning something new here. Thank you. Will definitely look into this.

Question:
1. P1A58 code howvere, it not related to the DPF... its related to the NOx converter. How would a mod like this help with the P1A58 issue?
2. Would doing a mod like this allow the car to still pass emission testing?

Zebby said:

It means getting rid of the inner part of the DOF and leaving just the shell. Then getting a tune like Malone to tell the ECU that thee is no DPF.

Click to expand...

i'm seconding dbbyleo's question above mine. i saw this post and was wondering if it'd be possible to gut the DPF and NOx converter (or replace it with a straight pipe made to look like a converter) so that the car may pass the visual test. is this something you've done? know someone who's done it successfully?

Update: My car is still at Audi. Latest from Audi is:
They have failed to resolve the P1A58 code with 2 regen attempts. Audi HQ advised them to do it a 3rd time in which it has failed again. I'm told the issue has been "escalated at Audi HQ" as to what the tech should do at this point.

[Recall that they had just replaced the NOx converter 6000 miles ago].

After doing a bunch more research on my own, I have to admit my driving habits likely contributed to this. I've always "babied" my cars - not driving them hard, always looking to extend fuel economy etc; I always let my cars warm up... and because "it seemed like these TDIs took longer to warm up compared to my gas cars" I actually would let it sit idle warming up anywhere from 10-15 min every morning.

I'ce read since then that both of these habits contribute to soot build-up.

A local diesel shop confirms this. He said it doesn't matter which make, Chevy, Ford, Dodge, VW/Audi... all diesel with emissions controls like these are susceptible to this issue. "They see it all the time" especially with people who buy big diesel trucks "for show only" and never put any real load on it, like towing.

Update: Just got my car back from Audi. After several (5 times) failed attempts to regen and fix the P1A58 code. On the fifth try, the check engine light came on - P13D4 and P13D6. They couldn't tell how this was related to the P1A58 (NOx regen required), but replaced Cylinder 3 glow plug and pressure sensor. With the MIL off, they took it for a 6th attempt to regen. Finally, after putting on over 500 miles on my car, the DPF warning light went off.

I got the car back home. I wanted to check for myself so I hooked it up the VCDS. And sure enough... there are no malfunctions in 01 - Engine.

I checked the DPF stats...

Oil Ash Volume (241.1): 168ml (car has 148K miles) ... from what I this is really all just calculated on the mileage of the car.

Soot Load Calculated (241.2): 7.2g ... from what I understand, this is a good indicator of when I should take the car for a "burn drive" (ie drive in sport mode intentionally) for passive regen... i think I read at 20g the car will do an active regen (but not positive).

Particulate Filter Differential Pressure: 8mbar (@idle), 18mbar (@2000 rpm - stationary) ... from what I understand, this is really the indicator of how clogged your DPF is. Anything above 27mbar would indicated a very clogged DPF and by then, there may be all sorts of DPF/MIL light on and fault codes.

My problem is ... all these stats is this is related to the DPF, not the NOx cat/storage/converter. Does anyone know what/where in VCDS to get measurements of the conditions of the NOx?