2.0 TDI (BMN) Are your PD elements clogged or misconfigured?

Hello everyone,

I actually signed up months ago specifically because of the problem described here. However, I wanted to take care of a few things first before posting… and I know that, from an economic perspective, the mileage makes it seem pointless for many people. But I'm attached to the car…

I drive an Audi A3 Sportback 2.0 TDI PD 125kw (BMN) Quattro. And for some time now, I haven't been getting the performance I should be. Unfortunately, it's a bit more complicated to explain. So, please excuse me in advance if this gets a bit lengthy... And to add to that, the more I read about the topic. The suspicion that I was originally on the wrong track becomes all the greater.

I'll try to describe everything in chronological order...

Sure, here's the translation:

"First of all:"

The car now has a mileage of 260,000 km. It has been chipped since the beginning (approximately from 50,000 km). Overall, it drives very well, but it feels like it's missing about 20% of its power. Otherwise, it's in excellent condition. The top speed, with a lot of acceleration, is around 210-220 km/h according to the speedometer. Originally, the speedometer indicated a top speed of 235 km/h, and it would reach the speed limiter in 6th gear (no, I didn't do that regularly... maybe 2-3 times throughout the car's life so far!).

All maintenance has been performed... the vehicle has been driven primarily on long-distance trips for approximately 75% of its lifespan. The intake manifold and EGR valve are accordingly clean, or have been cleaned again.

- At approximately 65,000 km, the piezoelectric injectors became clogged for the first time because Audi had simply installed a map update on the modified engine control unit... Audi cleaned the piezoelectric injectors free of charge and "fixed" the issue.

- At approximately 90,000 km, I received a new cylinder head free of charge due to coolant loss. It was very quiet for a long time after that.

- At approximately 186,000 km, Audi replaced the PD fuel injectors completely free of charge (and as a preventative measure) as part of a recall campaign.

- At approximately 205-210,000 km, my DPF reached the end of its life, and the problem was then resolved... I won't go into detail here about the regular differential pressure sensor replacement procedures (which I've experienced roughly every 50-60,000 km).

- At 255,000 km, I replaced the membrane for the crankcase ventilation system in the valve cover. The car started consuming oil around 210-220,000 km (approximately 0.75-1 liter every 4,500-5,000 km). The oil was collecting in the lower part of the intercooler hose, directly at the intercooler. "While this reduced the oil consumption, it didn't completely eliminate it... previously, the car consumed approximately 0.5-0.75 liters of oil every 30,000 km!"

- At 260,000 km, I recently replaced the turbo (including the oil lines) with a modified stock turbocharger from Z-Turbo. The old turbocharger was quite worn out by then. And the suspicion that the remaining oil consumption was likely due to the turbocharger... However, I haven't driven the car enough with the new turbocharger to say how the oil consumption is now.


What remains after all these modifications is a loss of power. This is barely noticeable in the lower gears, but quite evident at higher speeds... overall, the car feels less responsive above 3000 RPM than it used to! And as mentioned before, the full top speed will not be reached either...


What I had already resigned myself to was that I would have to have the DPF elements cleaned again. This is probably due to the ordeal with the full DPF at around 210,000 km and the oil in the intake system. They're probably stuck again!
"Yesterday, I also did a test drive and read out the lambda values in 4th gear at 3500-3800 RPM, logging them. I've attached the log... and if I'm reading it correctly, I have a lambda value of 1.41-1.44 in the range of 3500-3800 RPM in 4th gear. According to the information I've found, the value shouldn't be higher than 1.38." And that would likely be borderline and suggest a blockage of the PD elements.


During further research on this topic within the forum, I came across the "injection timing" setting for PD elements. And then it dawned on me that when the PD elements were replaced, they probably weren't adjusted correctly. Now, I actually have two more things to check or address: cleaning or replacing the injector sleeves for my PD elements, and verifying/adjusting the injection timing. Correction of injection time.


Now, to the actual question...

Does anyone in the Düsseldorf/Ruhr area have experience with this? And could you possibly offer some support? Or does anyone have any tips on how I can narrow this down further? Through potentially different values in VCDS?


You're very welcome, and best regards.

Florian.

Hello,

Less is sometimes more, especially when it comes to logging.

See:
Proper logging with VCDS

The lambda value seems to be too low at full load, which means there is a lack of power. PD injectors can become carbonized if properly adjusted and fuel supply is adequate (check the diesel filter!).

Best regards, Rainer.

Hi,

I also used to have a 125kW PD engine in my car, specifically in an A4 B7, which is essentially the same engine. I also experienced the problem of it losing power at higher RPMs. Here's a video: https://youtube.com/shorts/3lGSBAfu8lk?feature=share

Initially, the suspicion fell on the DPF, but the problem persisted even after we temporarily removed the DPF from the turbocharger for testing. It also couldn't reach its optimal RPM as quickly, even in neutral (and therefore failed the technical inspection).

The diesel filter was replaced, and suddenly the problem was gone. Additionally, there was a cracked intake manifold, but that wasn't the solution to the performance issue. It sounds like the same problem you're experiencing, especially since it happened at 260,000 km.