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Old 12-30-2012, 07:20 PM
robertobaggio20 robertobaggio20 is offline
Location: earth
Join Date: Oct 2009
Posts: 3,403
Mein Auto: car
Thanks for the writeup Steve. I think you and your indy is right.. Just read through the manual and it says this :

Residual pressure, checking
For quick restarts and to avoid vapor lock when the engine
is hot, the system is designed to retain fuel pressure after the
engine has been turned off. This residual pressure is primarily
maintained by a check valve at the fuel pump outlet and the
fuel pressure regulator. The fuel pump check valve is not serviceable
as an individual part.

So there is a check valve at the fuel pump. I believe that when fuel return pressure disappears, as when a hose somewhere bursts or is disconnected, the check valve notices this and stops the fuel pump from functioning. This is probably a safety measure. However i should think that the current to the pump remains live. And I am a little surprised that this happens when we are at key2. Perhaps because the fuel pressure regulator does not function because the engine is not running (the fpregulator needs engine vacuum to function), there may be some version of pressure detection that kicks in at the pump and causes it to go into standby mode or stop functioning altogether..


Last edited by robertobaggio20; 12-30-2012 at 07:21 PM.
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