It seems that every time I open the 'diesel' cap to the tank I hear an inrush of air. What is causing that, a blocked vent tube? If I do nothing, would the tank collapse due to vacuum when I run the tank dry/very low?

Your advice is appreciated.

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Not MBZ nor A/C trained professional but a die-hard DIY and green engineer. Use the info at your own peril. Picked up 2 Infractions because of disagreements. NOW reversed.

W124 Keyless remote, PM for details. http://www.peachparts.com/shopforum/mercedes-used-parts-sale-wanted/334620-fs-w124-chasis-keyless-remote-%2450-shipped.html

1 X 2006 CDI
1 x 87 300SDL
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