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?