Now this bl**dy car won't start - PLEASE, PLEASE HELP

[doony]

As you may have read I've had problems with this car, MAF sensor, replaced, EGR, now blanked, now the LAMBDA sensor says NOT PRESENT...
well that's one side now we went on a trip this weekend, about 125 miles, car runs sweet as but the management light does come on occasionally, on the last day before coming home the car wouldn't start, all lights present and correct, turn key, nothing...no clicking, not whirring, nothing!!!

The lights go out while you turn the key but nothing mechanical happening at all except when you look under the bonnet the little thingy by the throttle cable moves a little bit.
Got a couple of guys to push and she started no problem then drove the 125 miles home, but won't start again.

Plugged in OPCOM, sensors MAF and O2 not present?!?!? I give up, this car drives great but is giving me soooo many problems.
I've recently started a new job which is a 50 mile round trip, this car is giving me sleepless nights, PLEASE HELP ME!

[doony]

UPDATE: Just put a meter across the battery, which reads 12.75, when the ignition key is turned the voltage doesn't drop...I think it should, could be wrong though.

[jayybull]

does the starter motor click at all?
i had a problem when i put my c20let in my engine and started first time there was no clicking from the starter motor, well no noise at all then we wiggled the wires then it started to make noises but wouldnt start as i had a faulty crank sensor (02 sensor)

if its saying MAF take the wires off and give the terminals a clean if u say u recently replaced it, try that, if not turn ignition on 25times to reset ecu and try see if it starts, sounds silly but it will reset the ecu not relising the maf sensor is at fault n possibly start but will come back with another reading then u can double check, but then if nothing after all that go get a crankshaft sensor if u still got nothing but be warned the 02 sensor always shows up for some reason