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Jay
Jay, Nissan Technician
Category: Nissan
Satisfied Customers: 18890
Experience:  20+yrs experience with Nissan & Infiniti Trained & Certified.Currently still working for Dealer
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97 Nissan Maxima: Theres no fuel pressure and no injector pulse

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97 Nissan Maxima. Will not start. There's no fuel pressure and no injector pulse. If I jumper the fuel pump at the relay, the fuel pump runs, however the vehicle still will not start.
Hello and thank you for using JustAnswer.com

Did you check all fuses?

Let me know, thanks Jay!
Customer: replied 6 years ago.
Yes I did
Are you a repair shop?

Let me know, thanks Jay!
Customer: replied 6 years ago.
yes
Well lets go after this problem in two ways. Since the fuel delivery system and the injector pulse are two separate circuits lets check them separately.

First, do you know if you have voltage at the fuel pump fuse and at the pump?

Let me know, thanks Jay!
Customer: replied 6 years ago.
Theres no voltage to the pump and all the fuses were good. I tested the signal wire from the ecm to fuel pump relay and it was good, so then I tested one of the injector driver wires from the computer to the appropriate injector and it was good too. That's why I thought the ECM was bad so I got a used one, plugged it in, and I'm still dealing with the same problem.
Is there any after market alarm on this car?

The factory security system on Nissan's kills injector pulse. But doesn't kill the pump.

At the Ecm, ohming pin 11 to ground, and turn the key on and cranking, do you have continuity?

Let me know, thanks Jay!
Customer: replied 6 years ago.
What color is pin 11 and where do you start counting from? As I'm sure you already know, its pretty difficult to test the wires at the ECM on these things, they're all bunched together and overlapping.
Yeah, I normally take the back cover off and back probe them since my t-pins fit better in the back. Your looking for a Black wire with a pink stripe. B/P wire Here is the Ecm connector configuration. I need to run out for a few. When I get back I will check in with you and get back to you.graphic


Thanks Jay!
Customer: replied 6 years ago.
Ok there was no continuity when I ohmed out the wire and cranked.
Did you replace it with a used ECM?

Let me know, thanks Jay!
Customer: replied 6 years ago.
Yeah but I hooked the old one back up because I didnt think it was the problem.
Lets try this. Jump pins 3 and 5 at the fuel pump relay and see if you have your 12 volts at the pump. then ohm pin 2 at the relay to pin number 11 on the Ecm. Here is the wiring diagram to help. graphic

I am sure you have the diagram, but if you see what I see maybe we can figure this bugger out.

Thanks Jay!
Customer: replied 6 years ago.
Ok, sorry it's taken me so long to get back into this car. If I jumper the relay, the pump runs, and I also have continuity for that wire. Next?
Customer: replied 6 years ago.
Ok, sorry it's taken me so long to get back into this car. If I jumper the relay, the pump runs, and I also have continuity for that wire. Next?
Customer: replied 6 years ago.
Ok, sorry it
Customer: replied 6 years ago.
Turns out this vehicle is a complete electrical nightmare. But I found out there was no power to the computer via pin 24 (Voltage from ignition switch, so I ran a new wire and everything seems ok now. Thanks for all your help. I will let you know if I have any other problems.
Customer: replied 6 years ago.
I'd like to accept your answer for all your help, so please repsond so i can. Thanks.
Sorry to hear about the electrical nightmare on your car. Hope everything works out. Feel free to return if you have any more questions.

Thanks Jay!
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