Starting woes

[the_youth]

Started this weekend to give the M some much needed love having decided to keep her long term.
Wheels off and gone for refurb (originals and BBS CHs). Stripped a spare set of front calipers ready for a refurb and doing the same with rears. Have full service kit (all filters, oil, coolant etc...) and probably going to polybush it and may even consider some HSD coilovers.

However, today she decided not to start so I could warm her up and drain the oil.

Cranks over but seems like isn't fuelling. I suspect the fuel pump (fuses fine). The only odd thing on last time I ran her (just before Crimbo) was the fuel reading dropped to zero momentarily so points to sender.

Anyone experienced this sort of thing before? Any pointers?

Also, if I replace the pump (probably will if it turns out to be the case) has anyone used walbro? I think the gss225 would do but hear that the in tank pipes may need to be longer as the unit is shorter? Recommend place to but? Any other bits needed?

Finally, anyone running with waterless coolant? Looking at this as a potential option....

Thanks for any info in advance.

[the_youth]

Bit of an update.

Last night I took the filter off and replaced it. Nothing unusual to report.
Checked the fuses (13 & 18) for the fuel pump and both are fine.
Swapped the horn relay with the fuel pump relay and still nothing.
Plugged it up to my laptop no no errors logged.

I cannot hear the pump starting at any point and have tried with the fuel cap off. Could be a problem with the pump or perhaps immobiliser woes.....
Anyone recommend a quick way of checking the pump? I'm loathed to spend £400 for a new pump from BMW to find out it is something else!