My 2004 g35 coupe has gotten to where the brakes pulse after I hit the pedal. It does so hard enough that the steering wheel shakes and I get a major shake and rattle on the front end, even when not using the brakes. When I turn it off and restart the engine it's like it resets until I touch the pedal again. Sometimes I can hit the brakes pretty hard going down the road, it will reset then as well. I'm at a loss on why, and any help is greatly appreciated

 

Probably something triggering the anti-lock brakes. In the meantime for safer driving you can disconnect the battery, then unplug the ABS relay which sits directly in front of the brake booster / ABS valve block. It's a large black box with three harnesses plugged into it. Unplug them all. Then plug the battery back in.

This will disable ABS/VDC so you will NO LONGER have ABS while it's unplugged. Drive around and see if the vibration still persists, if it does then you have some sort of mechanical issue. Maybe a broken brake pad, maybe a loose bolt.

If the problem went away then you have some kind of malfunction on the ABS system, inspect for any obvious damage like the ABS sensors on the wheel hub, if it's not obvious then the quickest and easiest troubleshoot is paying a 1 hour diagnostic at Nissan / Infiniti.

I'm guessing your SLIP and BRAKE lights are turning on yes?

 

You need new rotors if the steering wheel shakes in the front, or if you feel the shake from the seats is your rear.