Audi5000TDI said:
(snip) It's very destructive to run your fuel tank way down.... you injector pump has to work too hard to draw fuel up the fuel column. Keep at least 1/4 tank in your fuel tank and this wont happen.
__. If I understand what you're saying, I think that this is wrong. The circulating pump ("pump 1") on the VE engine has to pull fuel through the filter. The amount of lift between full tank and low tank is insignificant in terms of the load on the pump. Of course, the PD with the lift pump is different anyway.
__. And Space, it's not that these pumps need to be primed but if you start them dry, you pump air into the injector lines before "pump 1" can lift and circulate fuel into the high-pressure side of the injector pump. Then, you have "air lock" (as W Dog very accurately describes, above). It's not really a "prime" thing. And, as described, it's really bad for these pumps to be run dry. (Again, PD's are different in detail.)
__. Still, I'd NEVER try to start a car with an empty filter. When I do my filters, I fill the hose from the filter to the pump before I attach it.
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