FUEL PUMP Q45 1990

[breda43]

I'VE CHANGE MY FUEL PUMP ON MY 1990 Q45 AND STILL WHEN I ACCELERATE IT ACTS AS IF IT WANTS TO DIE OUT BUT WILL PICK UP AGAIN.WHAT SHOULD I DO NEXT .I HAVE BEEN TOLD THAT USUALLY THE FUEL CONTROL MODULE GOES OUT OR SHORTS OUT ABOUT THE SAME TIME THE PUMP FAILS.

[maxnix]

Try reading Tangalora's benchmark fuel pump post in Infiniti Online Mechanic.

Please lose the CAPS key lock.

[PopPop]

I'VE CHANGE MY FUEL PUMP ON MY 1990 Q45 AND STILL WHEN I ACCELERATE IT ACTS AS IF IT WANTS TO DIE OUT BUT WILL PICK UP AGAIN.WHAT SHOULD I DO NEXT .I HAVE BEEN TOLD THAT USUALLY THE FUEL CONTROL MODULE GOES OUT OR SHORTS OUT ABOUT THE SAME TIME THE PUMP FAILS.

It's recommended U change FPCU when changing FP but, not necessary if U replace pump as soon as it starts to fail! If U continue to drive vehicle for a couple of months after U here it start to make noise under rear shelf then replace FPCU also. This is just to be safe but, some people get away with not replacing it and some don't! Your problem still may not be fuel related!

[breda43]

I'll lose the caps key lock and thanks!

[breda43]

Well what else do you suggest it is besides fpcu?

[txQ45]

If not the controller -- next thing is to do a balance test on the injectors If you have a Consult -- I do

[breda43]

Thanks and I will look at the controller board for burn marks ok

[5seryan]

Another cheap thing might be to change the fuel filter... that was one issue with my Q's acceleration issues. like $10 and if you havent changed it recently then you should do so anyways. PS if your FPCU is fried i have a working one ready to ship $65.. what i paid for it.

[Q45tech]

Burn marks usually show up on failed or repaired units............many times the strange intermittent units will look good.

Swapping out with a KNOWN GOOD/ BRAND NEW UNIT is the only final test that works..............junkyard used may just have other different problems.

Anyway steer clear of units with a discolored white Molex socket.

There is a reason dealerships insist on changing FP and FPCU as a pair......they have been bitten many times just changing the pump and the customer comes back in a month with similar symptoms.

[breda43]

This is some very useful info you've given!Thanks

[elwesso]

if the FPCU doesnt fix it, it could be a MAF related thing.