1996 q45 250K fuel pump not turning on

[IDRVQ45]

sorry for the duel post i posted in the wrong forum ( i'm new at this )

car stalled and died, would crank and start for a few seconds and progressivly got shorter (staying started ) with each crank. this sent me straight to fuel pump as problem - long story short - based on forum posts i could find - disconnected fuel pump and ran 12v direct and it did turn on - and yes prior to this it did hum ( actually i.ve had the hum for over 150K ) - i never said this wasn't my fault - anyway fuel pump runs ( i will change tho ) removed and checked controller all looks good no burns or overheating marks - based on post i tried the bypass to ground, still fp dead what i noticed however is about 5sec after i turn ignition the relay does click but when i checked voltages when it clicks it removes 12v from the fp ( yellow wire with blue stripe) - any help would be apreciated - thanx

[Q45tech]

Use the dealer diagnostic method........."take one look at high mileage and replace the pump [plus a new o-ring] and FPCU with brand new units".

While old pump out examine bottom tank with flashlight thoroughly looking for any tiny signs of runs or water bubbles in the pump filter catch basin.....replace tank or clean it completely.

[IDRVQ45]

thanx for your reply, i will order the parts, but just curious the issue with the relay removing the 12v line from the pump as opposed to applying it once it clicks on - is that right? or is it just symtoms of a bad controller?

and again thank you and all who post - very helpful.

[Q45tech]

The control has nothing to do with power on [+12 volt] relay that comes from ecu so that ecu can shut pump [and fpcu] off if the cranking is not successsful [engine doesn't come up to idle rpm] after a certain time limit............to minimize flooding.

[elwesso]

Ive seen the ground to the FPCU go bad before..... ID check that.