| Ta guys (no, not u timothy!)
Fuel starvation was my suspicion, but i'm not sure that ties up with the on/off power (it's either 100% on or 100% off, not nufink in between). Blew through the filter, a very technical check that was, and it seemed clear. No splits in the short tubes connected to the pump either. Could it be the relay, or is that only active when the pump is primed?
Pressure sensor - d'you mean the air pressure sensor?
If only it was a mechanical prob, then it'd be a piesh of pish! | 
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