Sr20det s14 rapid clicking on startup but not a bad starter?

[RobbieSS]

I've read just about every forum with this question and couldn't find my problem so here I am. When I try to turn over the car it either instantly rapidly clicks, or it makes an odd humming sound, or it actually attempts to turn over and then it dies and starts rapidly clicking. It ran about 2 weeks ago and then this problem showed up so I replaced the starter completely and the problem still persists. The battery is relocated to the trunk if that helps but its a brand new battery with brand new terminals. I should also mention that when working underneath the car on the starter I found about 3 different harness connections that weren't connected to anything and had nothing around them to connect to. Right underneath the transmission so I'm lost. Any help would be appreciated. I can also post a video of me starting it if that would help.

edit: I tested the battery when trying to start it and it dropped all the way down to 8v

[FaLKoN240]

Your starter isn't getting enough power to turn it over.

Make sure your grounds are good.

[RobbieSS]

I went through and checked as many grounds as i could find. All looked fine but i resanded the surface and the connections anyways and still nothing. Is there anywhere I could find a list of grounds?

[NukeKS14]

The FSM (https://www.nicoclub.com/nissan-service-manuals)

EL section.

How did you do the battery relocation? What gauge wire was used? How is the battery grounded in the trunk?

That your battery drops to 8v is telling. How many cold cranking amps is the battery rated for? You have to run a larger battery in the trunk than you could get away with in the engine bay.

[RobbieSS]

The FSM (https://www.nicoclub.com/nissan-service-manuals)

EL section.

How did you do the battery relocation? What gauge wire was used? How is the battery grounded in the trunk?

That your battery drops to 8v is telling. How many cold cranking amps is the battery rated for? You have to run a larger battery in the trunk than you could get away with in the engine bay.

I took 0 gauge and ran it through the passenger fender into the passenger dash where the ecu is under the floor mats into the trunk. I sanded down a piece of chassis metal on the left side and grounded it there. The battery is pretty massive its almost twice the size of the one i replaced it with but I can check, but I was just doing some inspecting underneath the car and found 4+ wires that aren't connected to anything: https://imgur.com/a/EsZ3Vwg

[NukeKS14]

Where does your 0 gauge power wire connect under the hood?

What is battery voltage when just sitting there ign off. Ign on?

How is your alternator wired up? Wondering if it isnt charging and you maybe have a dead battery.

I saw your posts about the wires that arent connected. I dont believe that to be your issue.

I would like to see how you wired in both your battery in the engine bay , the alternator power wire (big one) and find out if giving yourself a jump from the battery in your trunk allows the car to start. There are a few possibilities at this point.

[RobbieSS]

Where does your 0 gauge power wire connect under the hood?

What is battery voltage when just sitting there ign off. Ign on?

How is your alternator wired up? Wondering if it isnt charging and you maybe have a dead battery.

I saw your posts about the wires that arent connected. I dont believe that to be your issue.

I would like to see how you wired in both your battery in the engine bay , the alternator power wire (big one) and find out if giving yourself a jump from the battery in your trunk allows the car to start. There are a few possibilities at this point.

The one thing that confuses me the most is that it ran a couple weeks ago. It even drove.
My battery voltage is 12v with ign on and off.
The wires to the alternator look pretty fine to me but I'm going to test them anyways.
Heres a few photos of how I wired the battery up and do you mean jumping the battery or jumping the alternator. Thanks!
https://imgur.com/a/raB5lZ4

[NukeKS14]

Where do those 2 white wires w red stripe go? And yeah i meant trying to give yourself a jump start at the battery. With the car running you should be seeing 14v at the battery

[RobbieSS]

Where do those 2 white wires w red stripe go? And yeah i meant trying to give yourself a jump start at the battery. With the car running you should be seeing 14v at the battery

Those both go to the fuse box, and heres a better photo of the alternator wires, looks a bit musty to me.
https://imgur.com/a/vSsPVaA

[NukeKS14]

The one thing that confuses me the most is that it ran a couple weeks ago. It even drove.
My battery voltage is 12v with ign on and off.
The wires to the alternator look pretty fine to me but I'm going to test them anyways.
Heres a few photos of how I wired the battery up and do you mean jumping the battery or jumping the alternator. Thanks!
https://imgur.com/a/raB5lZ4

Another thing to mention, especially if the car sat for a couple of weeks, is you could have a drain on your battery as well. If you've got a sticky relay not letting go or another faulty electronic component it could be draining down the battery while it sits. It's tough to track down drains, especially smaller ones. It's a systematic process of pulling fuses until you find the suspect circuit. Typical offenders are head units/stereos and other aftermarket electronics that are improperly wired.

The way I have my battery relocation wired is an 0-gauge wire up to a terminal block like you have. Then I have a 4 gauge wire going directly to my starter and the other running straight to my fuse box.

I found a couple of old pics from when I rewired my alternator if it'll help you at all. I replaced the ground and power wires between IM and fusebox. I realize you're running an SR but should be the same (for the alternator power.)

https://i.ibb.co/0nDxnKL/W1.jpg (https://ibb.co/6ynky8S)
https://i.ibb.co/fGJbmk5/W2.jpg (https://ibb.co/93PJRbL)

Don't mind the mess. One of the previous owners swapped a 2JZ into it and went nuts-o with the sawzall and butchered the fuse box.

[RobbieSS]

Another thing to mention, especially if the car sat for a couple of weeks, is you could have a drain on your battery as well. If you've got a sticky relay not letting go or another faulty electronic component it could be draining down the battery while it sits. It's tough to track down drains, especially smaller ones. It's a systematic process of pulling fuses until you find the suspect circuit. Typical offenders are head units/stereos and other aftermarket electronics that are improperly wired.

The way I have my battery relocation wired is an 0-gauge wire up to a terminal block like you have. Then I have a 4 gauge wire going directly to my starter and the other running straight to my fuse box.

I found a couple of old pics from when I rewired my alternator if it'll help you at all. I replaced the ground and power wires between IM and fusebox. I realize you're running an SR but should be the same (for the alternator power.)

https://i.ibb.co/0nDxnKL/W1.jpg (https://ibb.co/6ynky8S)
https://i.ibb.co/fGJbmk5/W2.jpg (https://ibb.co/93PJRbL)

Don't mind the mess. One of the previous owners swapped a 2JZ into it and went nuts-o with the sawzall and butchered the fuse box.
Yeah that would make sense if the battery was being drained but im not sure if thats my case. I tried jumping the battery with my other car and nothing changed so I think theres a short somewhere but I can't find it. But it could be the wiring to my fuse box and/or starter