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How much air is okay

1784 Views 4 Replies 4 Participants Last post by  LIQUIDSILVER
I saw that the fuel lines going to the fuel pump sometimes get an air bubble. I never bothered with it because the car runs fine, but how much can get inside the fuel lines without stalling the engine? If it gets worse I want to fix it now.
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I think a few bubbles are okay, if you are talking about the older VE direct injecion, the injection pump purges air out. too much air can make it stall, but I imagine a few bubbles are okay.
His profile says 2001 so it's a VE. Check the fuel filter o-ring for proper seating. An air bubbles when the car is off sometimes happens. Ideally there should be no air bubbles at all. There is also the possiblity of the fuel pickup in the tank letting in air or maybe a loose hose?

If it gets to the point of hard starting, then you know it's an immediate problem. In the meantime, check the fuel filter o-ring and hoses.
A lot of the times the air bubbles come from the T on top of the fuel filter, it could have a crack or bad O ring,,,,there are other times that it comes from the water drainage valve at the bottom of the fuel filter,,,,, you will get rid of those air bubbles if you install a Lift pump most likely.
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