Thread: Major ignition issue, battery drops to 9v, and ground off distributor gets very hot.

I think something is finding a ground through the distributor grounding wire that shouldn't. Where is the distributor grounding to? It should ground to the intake manifold, right? And your new wire also grounds to the intake manifold, right? Or do you have it grounding to the battery or somewhere else?

The starter does ground through the block, which grounds to the chassis and then the negative battery terminal through a 4-gauge wire at the thermostat housing*. That ground is known to fail on '90s vintage Nissans like clockwork. It's possible the starter is trying to ground through the distributor ground somehow. Try grounding the engine block to the negative battery terminal directly with a set of jumper cables. Then do another test of the cranking behavior.


*There is also a ground from the exhaust by the cat to the chassis which is probably long gone.

Quick background, I am running a 96 IM on my 2000 RR motor. The grounds on the IM weren't the same. I in turn grounded them to the firewall. They have been this way for 2 plus years and over 50k since boosting the car. When I reground the dizzy ground I ran it to the ground by where you intake would be.

I have also relocated the battery to the trunk. I did that with 0 or 2 gauge wire, I forget exactly what it was. The battery and negative cable were just replaced. The negative cable ground to the inside of the trunk well kinda where the spare is.

The ground that fails, is that the one on the block?

True, the car is 13 years old.

Both dizzys are good. I can test good voltage, continuity, and ground. It's like what Ben is saying, like the starter ground is failing and trying to ground out to the dizzy.

Yes, that's the one that fails on people. It goes from the thermostat housing on the block to the frame rail near the stock battery tray. It can look fine, but it's going to be corroded to shit on the inside more than likely.

To do your test (with the battery in the trunk) I advise you ground the engine block to the negative battery terminal still. This might take two jumper cables hooked together to reach the battery.

OK, I found that ground, it's in a different spot then you aer mentioning. on the B15 it goes from the trans to the body right under the fuse box. I pulled that and will be making a new one today. I also did the block to battery negative and boom, car fired right up. So i know now it's the main ground between the motor and the body. Thanks Ben for all your help, I really needed that other set of eyes for say as I was just running out of steam.

Good to hear you're on the right track now it seems. Good luck.

Ground wire between block and body replaced, car fired up and runs like normal. Thanks for all your help.

Yep, bad ground or power cable will be the only cause for them to be getting that hot. Ive seen some pretty funky stuff happen on some of the dodges I work on at work. Had a durango that was having weird starting issues. What it was was the block was soo corroded and rusted that all the ground points were barely getting any continuity. The main ground cable was corroded badly. Ended up moving the main ground cable attachment point from the block to the head and cleaned all the other ground attachments to the block and chassis. Main issue was the stud in the block the ground goes on was corroded/rusted into the block and wasnt giving a very good ground at all. To the point where most of the electronics on the vehicle would not work and starter engagement issues. The cables like yours would get very very hot. In short, make sure your power and ground cables are in good shape and it will save you a lot of headaches.

I guess it is about time for all the B15s in existence to start having this same problem.