Sorry I am a Mustang guy, but I am trying to help out a buddy who has a 1990 300zx 2+2 auto. I replaced his fuel pump and fuel filter, and the pump is getting juice back to it, but it is not turning on. I made sure that the fuel pump relay switch was good (plugged in tightly, and getting power to it) and also checked all the fuses I could find, although I couldn't find anything specifically for the fuel pump. All the fuses were good, the pump is getting juice, but not turning on and the car won't start, relay switch is good, does anyone have any suggestions? Could it be the fuel pump control unit? I have never heard of a FPCU and have no idea where it is on his car! I mainly work on my Mustangs, so this is foreign to me. I appreciate any help that anyone could give me! Thank you!


Jacob

 

The fuel pump control unit is under the panel behind the driver's seat on the 2+0, so I'd imagine it's under some panel behind the rear seats on the driver's side in a 2+2. And they are problematic on early Z32's, so I would say it is a prime suspect. Remove it, disassemble it, and find the part of it that fried... it'll be obvious.

common shortage example (but not the only cause for a dead FPCU)

 

Awesome thank you for the quick response to my question. Do you think that the FPCU is a good suspect here? With the fuel pump relay should all of the "pins" be getting power? Only two of them on the one side are, but I thought that is how it is supposed to be. Thank you for your help!

 

I actually said it's a prime suspect. lol

As for the relay, only 2 pins should be getting power, so that is fine.

 

Okay, sorry I missed that. Thank you for your help ZLover, hopefully we will get a chance to work on it real soon.


Jacob

 

Thank you so much ZLover. I just wanted to let you know we got it fixed. We took out the FPCU and nothing looked wrong with it at all, but we had exhausted all other options so we wanted to replace it. We went on Craigslist and found someone local who was parting out a 2 seater 91 and got the FPCU for $20. It fixed the problem! Thank you so much again, we appreciate the help.

 

No problem.