Need help from anyone I am stumped

[Niterider73]

hello I have a few questions about my z i recently purchased, I believe yall have the knowledge of z's to help me out
1. the fuel pump was replaced along with my tank sealed when the guy i bought it from put it all back together the digital fuel gauge no longer works. the low fuel light and the DTE still function but the gauge and number of gallons does not register what could this be?
2. what is the silver box that is plugged into the fuel pump and sending unit in the trunk?
3. the new fuel pump constantly stays on even when just turning the ignition on, but not cranking the car, is that suppose to happen? if not could a relay be bad or something?
4. the adjustable suspension functions for about 15 seconds (i can hear it when i select each, I can hear it in the suspension) but after the 15 or so seconds it starts to blink. Could this be worn out shocks?
5. my avg. speed does not work just shows two little flat lines, I have turned it off and turned it back on but it dosent register. What could this be?
6. Last question and is one of the most confusing so bare with me here, I dont know if my headlight switch is bad or not, reason being I have no interior lights, parking lights, or tail lights, I have brake lights though. If I turn to the parking lights on the switch nothing comes on at all, not even the animated voice dosent say anything about the lights being on with the key out of the ignition. Now if i turn to the headlights selection, just my headlights come on and its only the dims if i turn to brights, i have a headlight out light come on in the dash, no blue brights light showing, and if i turn on my brights the flip lights just go nuts. I have fiddled around with trying out different things and I have had my parking lights, interior, tail lights, and the voice come on. I accidentally stumbled upon this by replacing one of my tail light bulbs it required a 1157 bulb (two prongs on the end) and i was trying to put in a 1156 bulb (one prong on the end) in I had the brakes pushed in at the time, and when I put the 1156 bulb in all of my interior, parking, tails and the voice were on. What In the world could this be??? Please I need some help with these problems. I love my 300zx and want to restore her soon!

[evildky]

1. sounds like a bad sender, mine only worlks on the last quarter tank (analog)
2. I don't know what you're talking about there, mine had no such box, sender and pump have seperate harnesses and only the sender is accessible through the access pont, the tank has to be dropped to access the pump IIRC, no silver box that I can recall
3. did he simply replcae the pump or did he monkey with the wiring? have you checked all the fuses
4. I never had a car with working adjustable suspension so I'm not much help there, although I'd suspect the control module
5. speed sender? wiring?I never had digital dash so not something I have any experience with
6. sounds liek the switch is bad, it's a fairly common issue, when you put the wrong bulb in it likely briidged the stoplamp power to the tail lamp circuit

[AZ-ZBum]

hello I have a few questions about my z i recently purchased, I believe yall have the knowledge of z's to help me out

Sometimes.

1. the fuel pump was replaced along with my tank sealed when the guy i bought it from put it all back together the digital fuel gauge no longer works. the low fuel light and the DTE still function but the gauge and number of gallons does not register what could this be?

Doubtful it worked before he took it apart then. But.... Define "doesn't work". Does it not light up ever? Does it provide an incorrect reading? Does it ever provide a reading? How many gallons are you putting in when the low fuel light comes on? Does it light up when you run the dash through the test mode? Are any of the other gauges working or not working?

2. what is the silver box that is plugged into the fuel pump and sending unit in the trunk?

Part of the signal conversion for the digital dash. Without it, the dash won't know what the appropriate signal is to display and won't display anything.

3. the new fuel pump constantly stays on even when just turning the ignition on, but not cranking the car, is that suppose to happen? if not could a relay be bad or something?

It should run for about 10 seconds or so after you turn the key to the "ON" position, but before you start the car.

4. the adjustable suspension functions for about 15 seconds (i can hear it when i select each, I can hear it in the suspension) but after the 15 or so seconds it starts to blink. Could this be worn out shocks?

You should NEVER hear them run. Ever. I'm not sure what you're hearing. Do you have the original shocks? It's unlikely they're any good anyway.

5. my avg. speed does not work just shows two little flat lines, I have turned it off and turned it back on but it dosen't register. What could this be?

It is supposed to take about 30 seconds of driving to register. If there is an issue with the speedometer or clock, it won't work.

6. Last question and is one of the most confusing so bare with me here, I dont know if my headlight switch is bad or not, reason being I have no interior lights, parking lights, or tail lights, I have brake lights though. If I turn to the parking lights on the switch nothing comes on at all, not even the animated voice dosent say anything about the lights being on with the key out of the ignition. Now if i turn to the headlights selection, just my headlights come on and its only the dims if i turn to brights, i have a headlight out light come on in the dash, no blue brights light showing, and if i turn on my brights the flip lights just go nuts. I have fiddled around with trying out different things and I have had my parking lights, interior, tail lights, and the voice come on. I accidentally stumbled upon this by replacing one of my tail light bulbs it required a 1157 bulb (two prongs on the end) and i was trying to put in a 1156 bulb (one prong on the end) in I had the brakes pushed in at the time, and when I put the 1156 bulb in all of my interior, parking, tails and the voice were on. What In the world could this be??? Please I need some help with these problems. I love my 300zx and want to restore her soon!

This is generally headlight switch related, but first you should check the fuses. Specifically, check the ILL fuse.. Make sure all the bulbs are correct. No. Using a single fillament bulb in a place where dual filament bulbs are required WILL NOT WORK. Might as well try deep frying that Thanksgiving turkey in 10W30. You got all those errors and warnings and stuff because you were using the wrong bulb. The car freaked out. Don't do that.

[Niterider73]

as far as not working I bought the car about a month ago and he replaced the fuel pump and had it sealed about 4 months prior and after that the gauge never lit up at all, no flickering, no nothing. and I know the low fuel light and the DTE is accurate bc I pulled the sending unit out and played with the float on the slide, and the DTE would increase and decrease as far as miles. and the low fuel light would come on if i put it in an empty spot on the float. No it also doesn not light up when I do a test on the dash, but all of the other gauges work properly except my avg speed, I dont think my AVG speed is working either bc i have drove the car and it never registers, but the speedo and the clock work properly, guessing maybe a sensor? When he put the pump in no he didnt hack or fiddle with the wiring as far as i can see jsut plugged it up and now it constantly wants to stay on, could this be a faulty fuel relay?
I can hear the shocks when I adjust them just barely when the car isnt running, its almost like an electric motor turning.
but it works for about 15 seconds and then the go to blinking and after that when i select another firmness i cant hear it run n e more, something tells me that they are leaking and it may set off like a sensor or something to cut it off.
Ok im gonna replace the sending unit and the converter box along with it bc the box is rusty on the bottom, so no telling if it still even works or not. Now as far as replacing the headlight switch do i have to pull the steering wheel off? I just remembered also before i bought the car the battery overload, i guess its a relay or something its next to the battery in a box with a wire comming out of it was toast, what could cause this? i have a 40 amp fuse in there to replace it. Also one more thing, can yall guide me in the right direction as far as finding good reasonable priced parts for my restoration? Such as: Dash, various switches, ect?

[evildky]

on the parts:
MSA (zcarparts.com)
blackdragon
courtesyparts.com
z31parts.com
your local nissan dealership
junkyards
classifieds on z car forums
you local z car club (zcca.org)

[AZ-ZBum]

If the gauges aren't lighting up, it's generally the power supply. Every once in a while, there is an issue with the actual instrument cluster. Yours might be one of those times.


It sounds like your shocks are toast. Time for new ones. No. You can't buy factory replacements at the Nissan dealer any more. Yes. You will be losing that in car adjustability.

Yes. You have to remove the steering wheel to replace the headlight switch.