Subject: EGR deactivated / Turbocharger whistling audibly at idle | Posts 16+

I temporarily disabled the EGR system for testing purposes.

I immediately noticed the whistling sound of the turbocharger when the engine was idling!
What do you think about this??? I'm not entirely sure (others here probably know better than I do...), but is the EGR valve actually open at idle?

I'm not entirely sure (others here probably know better than I do...), but is the EGR valve actually open at idle?


Yes, in the case of the ASV, the EGR valve is open at idle and closes after approximately 2 minutes.

I observed the same thing as 'Brösel.'

Nachdem ich gestern den Turbo erneuert habe und die ARG tot gelegt habe, höre ich den Turbo deutlich beim anfahren ab ca. 1100 U/min. Beim schalten ca. 2000 U/min ( Motor kalt) ändert sich der Sound syncron zur Drehzahl. Nach lesen des Beitrags habe ich dann heute die AGR mal Probehalber wieder in betrieb genommen und jetzt ist der Turbo bei weitem nicht mehr so deutlich zu hören. Weiterhin kommt es mir so vor als wenn der Motor jetzt mit AGR etwas weniger Leistung hat. Is that correct?

So, should I remove or replace the EGR valve? Will it damage the engine to drive without an EGR valve?

I would prefer to drive without the EGR system, especially after seeing how much soot buildup had reduced the cross-sectional area of my intake manifold.

After I identified the catalytic converter as the cause of the performance loss, I now have a new one. Does driving without the EGR valve affect the catalytic converter?


T4, year 1998, 2.5 TDI ACV engine, chip tuning, 298,000 km mileage, no oil consumption, turbo, catalytic converter, and exhaust system are new.

Here is a very informative article about the function of the AGR (Abgasrückführung) and how to disable it; please take a look. I think this should answer your questions; if not, you can ask again.

I don't think so, please provide a link.

Thank you!

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