Sticky residue in Bosch LDA

[Dan!]

Probably the seal between the fluid part of the pump and the lower lda housing is weeping slightly, letting veg get onto your lda and dry out/go sticky, which is the residue you are getting. The seal will get progressively worse over time, but will probably be fine for year or so. They dont tend to leak too badly really, alot just seep for years and years. Keep an eye on it once a month or so though, and check that the lower lda housing (under the diaphragm) isnt filling right up with veg/diesel. If it is pull your pin right out and use thin strips of kitchen roll to soak the fluid up.