I have a 2003 G35 Sedan with about 187,xxx miles. Yesterday, I replaced the radiator as the original was cracked and spraying antifreeze everywhere. Today, not even a whole 24 hours later, I've come across another problem. I went to go drive my car earlier today. I turned the key and turned on the car and immediately noticed an issue. Normally upon start up, the engine runs at about 1200rpm until it is warm and then it falls down to 800rpm. Well, immediately upon start up, it dropped to 800rpm. It felt funny and sounded a little odd. I noticed the parking brake light and the battery light were both on. I then put my car into drive and the ABS, slip, and VDC off lights all turned on at the same time (battery and parking brake lights are still on). I tried to then move the car in drive but when I pressed down the gas pedal, nothing happened. The car went from 800rpm to 1000rpm but that was it. No matter what gear I was in or how much gas I gave it, I could only idle the car. I can still move the car but only at about 3mph while idling. Sometimes when I press the gas pedal and cause the car to rev to 1000rpm, the radio shuts off, which I thought was strange. Also, when I first turn the car on, for about three seconds I can rev the car freely, all the way to the red line. Then the lights turn on and the rpms drop to 800. It's almost as if the problem is electrical but also has to do with the braking system. I own a scan tool and I tried scanning the car for any codes and it didn't find any. I am completely stumped as to what the problem might be. I didn't do anything to the car and yesterday after I replaced the radiator, the car worked beautifully. Any input as to what might be causing this would be much appreciated. Thank you all.

 

The red BRAKE light is also a low brake fluid light.

Not that I think this is your issue, but is your brake fluid level ok?

 

Yes I read somewhere about that and the brake fluid was at about halfway so I filled it to the full line to be safe but that didn't seem to fix anything at the time. I just went and turned the car on today after it sat overnight and it's working perfectly fine again. I'm a little nervous about driving it because I'm afraid it'll decide it wants to stop working again in the Kroger parking lot then I'm stuck. But who knows, maybe that brake fluid was the problem and it just needed to sit overnight or something. Thanks for the reply! I'll be keeping a very close eye on this.

 

After looking around a little more, I found a 2 inch stretch of wiring leading directly to the braking system that is not wrapped up and sitting in a pile of wet dirt. I'm sure they're shorting out and causing all these issues. What should I do? Is this fixable? I'm going to attach a picture of it. Any help would be appreciated!

 

I would venture to say that could be an issue.

Grab a hairdryer or heat gun and dry that all out. Clean out the dirt as I think there are drain holes in the bottom of that chamber.

Peel back some of the wiring wrapping and look for damaged or nicked wiring. Depending on how bad it is, you may need to repair the wire, or just individually tape it up and then support the wires out of whatever water puddles up there

 

I'm having this exact issue. OP, were you ever able to solve the problem? Did it end up being the wires?

 

I did eventually figure out the issue! Sorry for never posting this. It was the alternator. A buddy of mine said he had seen something similar to this in a nissan before and told me to take the alternator out and have it checked at an auto parts store and sure enough the alternator was completely dead. Replaced the alternator myself and like magic the car was working fine and has been fine ever since.