Air Bubbles in Fuel Line: Causes & Fixes

Hello everyone, my question has probably been asked many times before... but never mind.

There are always air bubbles in the fuel line leading to the ESP, and I've read something about a seal or O-ring.

What should be replaced now? The small O-ring on the fuel filter, or even the ESP (Electronic Stability Program), or something else?



I'll look into the other issue regarding performance loss and increased fuel consumption this weekend... I'm curious to see what I find.

Best regards,
Mhernach.

I would start by checking the O-rings on the fuel filter. They sometimes get pinched during filter changes.

Es gibt auch komplette Filter die Müll sind (z. B. from ATU).

Best regards, D.