A6 96 No Power: Troubleshooting & Fixes

Hello from Italy, a compliment to your community. I have a question... My A6 96 AEL with 160,000 km sometimes experiences a lack of power (maximum speed 120 km/h), but it only lasts a few minutes, then everything is okay. The error memory is clear, and the turbocharger pressure is normal when the problem doesn't occur, according to the 1551 diagnostic tool. Could it be the EGR valve or the turbocharger? Can anyone help me?

What about the turbo boost if the engine isn't working properly? By the way, a lack of power with fuel from Italy seems to be normal; my former instructor (who was Italian) complained about it, and so did my father (when we had to refuel in Italy).

Best regards, WarLord.

Unfortunately, I can't keep the Vag 1551 or the pressure gauge for 2-3 days. However, the boost pressure seems to be zero because the engine runs fine, although it smokes normally or slightly less, but only produces 30-40 kW. The intake system and vacuum lines seem to be okay. It probably isn't a fuel issue, as the fuel quality isn't bad these days, and fuel problems usually cause different symptoms, such as hard starting or rough idling. Thank you anyway.

Hi,
hatte in Italien auch keine Probleme mit dem Sprit. Running as usual.
If you suspect a problem with the boost pressure, you should connect a boost pressure gauge; alternatively, you can use any pressure gauge. Even a temporary installation can be sufficient for checking.

Hi Ivanovic,

Since you don't have any further diagnostic options available.
Please check the wastegate and the EGR valve for smooth operation.

Hello from Italy, a compliment to your community. I have a question... My A6, 96, AEL, 160,000 km, occasionally has a lack of power (maximum speed 120 km/h), but it only lasts a few minutes, then everything is okay. The error memory is clear, and the turbo boost is normal when the problem doesn't occur, according to the 1551 diagnostic tool. Could it be the EGR valve or the turbocharger? Can anyone help me?

'Hi, I'm experiencing the exact same problem with my 1996 AEL-2.5TDI. Sometimes, when accelerating, it only reaches 120 km/h and doesn't go any faster. This lasts for a few hundred meters, and then it's fine again. Interestingly, this issue only seems to occur when driving uphill. I took the car to VAG for a check, but they didn't find anything. The error memory was clear, the MAF sensor is OK, the NOx sensor is OK, the boost pressure is OK, and the compression is OK.'
I'm just as clueless as you are. If you happen to find the cause, I would appreciate it if you could let me know.

The irony is that my A6 comes from Italy. I first registered it in Germany on January 30, 2004... but I don't think that matters!

Best regards,
Thomas.

Floor mat slipped under the gas pedal?

It sounds like it's in limp mode, for some reason, even though the error memory is empty. First, continuously monitor the boost pressure. It might be drawing in air going uphill. To check this, run the return hose with a suitably long, transparent hose all the way to the windshield.

Hi,

In the AEL (possibly also AAT) system, there's a small plastic hose that runs from the intake hose to a sensor or solenoid valve on the injection manifold, and it's located very close to the EGR pipe. In my car (and probably in others as well), this hose, after the cable tie used to secure it broke, came into contact with the EGR pipe and melted. The consequences were similar to the power loss described.

Regards,
Olaf.

It was the AGR valve. It's easy to get stuck when checking it, but it sometimes sticks closed at operating temperature. Now that it's fixed with a metal piece, it's okay, but the engine sounds different, more like a four-cylinder. What do you think about the howling noise in 6th gear at 1800-2000 RPM? Is it due to the gears?