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Old 29th December 2019, 09:35 AM
MikkiJayne MikkiJayne is offline
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Join Date: Jan 2012
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Quote:
Originally Posted by C4R 100N View Post
Is it normal for fuel to dribble out of there? I remember replacing the FPR on my A6 sedan and it was leaking out of that top tube pretty badly.
No, it shouldn't leak fuel from there. If it does, the internal diaphragm is split or perished and it should be replaced. Manifold vacuum acts on the back of the diaphragm in conjunction with the spring to ensure that there is a constant 4 bar across the injectors relative to the inlet manifold, rather than atmosphere (1 bar already).

I get easily mixed up about how it goes wrong without it connected - I think it runs lean, but I'd have to look it up to be sure. The ecu can compensate to an extent with the O2 sensors.
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