Fuel pressure drop and wont start.

[L18M]

woo.. found the problem. though was very mysterious. the fuel pump relay, switched the wires around a bit and works without fuel drop.

Very mysterious as was working fine before.
The joys of modified motors lol

Thanks for the input guys

[Arnie_O]

Glad your sorted.
Enjoy the car.

[shaunwil]

Good to hear you found it

Shaun

[Prof]

Could be that if you \'rewired\' the fuel pump - you may have taken a positive feed to the fuel relay from a positive that\'s switched out during cranking.
 
Normally in the fuel pump rewire, you keep the existing fuel pump wiring but use it to only drive the relay coil, and then use a beefy fused positive straight from the battery to the fuel pump (or to the fuel pump resistor relay block if you are keeping the 2 speed fuel setup), maybe you took a positive feed that\'s not on with all three key positions other than off?

[L18M]

Its a weird one prof as the fuel pump wiring was done before and worked ok. then randomly decided not to work.

I think there\'s a gremlin in my car continuously  causing me grief

[Prof]

You may have a faulty ignition switch, perhaps one of the 12v feeds is dropping when you crank?   you could test this by disconnecting the 12v to the starter motor temporarily, and measuring the 12v feed to your fuel pump relay when your ignition switch is in cranking position.  I used to have intermittent issue with wipers and roof motors not working and a gentle tickle on the ignition switch would have them working again...
 
If you are getting a solid 12v with the above test, then it could just be that the voltage drops so low during cranking that the relay drops out, could be a sign of a flat or dying battery.

[L18M]

ok thanks prof, will check it out once i get the car back