So over the past few days my R has really been acting up. First it melted the wiring harness below the box that holds all the relays. So I soldered the connections back together properly and rebuilt that portion. Starts up fine but the battery light and the abs light is on. So I go ahead and replace the alternator with a 100 amp Nissan Sentra one. Battery light and abs light go away but the car is running really lean. Idling and crusing was hitting 17.1 on the aem afr. So I replace the fuel pump with an AEM 320lph. Starts and runs fine for one night. Runs normal. Today on the way to work the stereo turns off, my boost gauge lights and dash lights and the car starts chugging like it has a dead battery. Idles at 500 rpm them 0 then 500 and so on and now it will not start. I'm have no idea what to do next to fix this. I am mechanically inclined so feel free to ask away about testing things. Any advice is appreciated. The picture is of the burnt harness before I fixed it
your harness must have burned somewhere else or your relays have burned at the same time. you should test all the harness on continuity mode (resistance) just to be sure it was repaired properly
When I opened the harness it was only the grounds that had burned. None of the striped wires were burned. Does that still make a difference?
bad grounds can causes a lot of problems like yours.
also did you solder every wires you cut before putting them back there ?
All the wires that got burned were taped and the ones that were disconnected got soldered and taped
there is your problem : never reuse the part of a wire that previously burned. if you test all the grounds that burned in continuity (ohm) you will find out that you get some electrical resistance in them. they should give you almost nothing because copper is a metal that gives almost 0 ohm when you test it
Here's what I have figured out. I had purchased a new battery before the snow flew from Canadian tire. It was one of their "better battery's". The car wouldn't start with that battery after I fixed the harness ( I assume I burnt a cell) so I put the battery I got with the car in. Started perfectly so I drove it but that's when I only got about 10 min from my house and it shut off. But I don't think that the charge from the alternator is going back to the battery because the voltmeter I use isn't showing any fluxuation of volts at the battery. It stays at a constant 11 volts. Even if I play the stereo I put in or rev the car the volts never change
if you start and the voltage doesn't go between 14 and 14.7 volts then maybe your alternator is busted. could be worth to remove it and take it to a rebuild shop so they can test it. most places offer that service for free hoping you'll buy another one.
I got rid of that kind of problem on mine. I use a alternator from a 2001 2.0l sentra, they are rated to 100 amp instead of 80 amp like the NX2000 alternator the gtir is using in stock form.
I have a brand new alternator from a 2001 sentra 100 amp so I know it's not the alternator. I replaced it no less than 4 days ago
check resistance between alternator hot terminal and positive battery teminal. also check the resistance between battery negative terminal and the chassis. if all checks with 0 resistance then move on to testing the regulator plug on the alternator.
I would really be assuming bad wiring to your regulator as you have had burnt out wires recently. Basically the ecu not able to tell the alternator to enable charge.
Good luck.
So I checked the resistance on the alternator ground and I got 178 ohms, is that even possible? And do I have to replace the whole wire or just cut the burnt section off?
The alternator shouldn't have a ground wire as it would ground through the metal case and through the engine? I could be wrong, but I doubt. Take a photo of said wire. Also you can get away with replacing a sections of wire as long as you cut away ALL of the burnt section and solder to clean wire, would definitely be checking wire resistances or voltage drops along the harness and finding out why the harness burnt up in the first place...
The wire burnt up due to the voltage regulator failing on the last alternator and sending wayyy to much voltage through the wires and the grounds couldn't handle it, after I fixed the harness the battery light was on so I know it was the alternator. I'll take a picture when I get home and open it up again
resistance of copper is supposed to be near 0 ohm, anything not around that will never be good
Hey just an update, ended up grounding the positive of the alternator to the chassis when fixing the wiring. Shoulda traced the wire back farther the first time. Problems fixed thanks for everyone's help.