Needle Valve: Does it also apply?

Hello fellow DIY enthusiasts!

I've been experiencing the following issue with my Audi 80 TDI, manufactured in 1994 and with 250,000 km on the odometer: At 140 km/h (5th gear), the power suddenly drops, and the car stops accelerating. If I briefly release the accelerator and then press it again, the car accelerates up to approximately 160 km/h, and then the same issue occurs again, etc. This problem also occurs when driving uphill, in 3rd and 4th gear. What could this be? Thank you in advance!

Best regards, Christian.

Okay: I performed the knock test for the NHG at 3000 rpm -> no knocking!!! So, is it the MAF sensor?

Hi.

I'm spontaneously thinking it's likely due to excessive boost pressure, which is causing the engine to go into limp mode with a reduced fuel injection amount.

Older TDIs will activate emergency mode as soon as the accelerator pedal is released.

Have the boost pressure read out during a test drive, or at least temporarily install a boost pressure sensor (LDA). The pressure should be approximately 0.9 to 1.1 bar under full load.

I'm less inclined to believe in the LMM, because you can't fix it by simply removing the gas.

Okay, so: a hose connected to the solenoid valve had a hole (it was worn through) -> it was replaced -> and now everything is fine.

Thank you to Ulf for the correct information!!!!!