I have a lowered G and my tires scraped the plastic guard and the whole guard came off along the bottom of my car and in my wheel welds, do I need to replace the plastic or can I ride without the plastic?

 

You don't NEED to, however as the name of the part implies it guards the underside of your engine bay and wheel wells from road debris, water, etc... You run the risk of damaging much more expensive areas if you run without them. If your G is running low enough to cause that kind of damage you may want to re-evaluate your ride height, driving style, or perhaps move to the Bonneville Salt Flats...

 

It’s not that the ride is that low, it’s more of I was missing the clips so it just hung because I never zip tied it to the holes

 

I would get one, it supports the front bumper and it keeps crap out of the bottom of your car. Last thing you need is a rock hitting your oil pan or your oil filter and causing it too leak.

 

Ahh, understood. Your initial post I had visions of you driving around with your G slammed to the ground. Yeah def. take the time to replace everything. The plastic retaining clips in the wheel wells are easily replaced either via Infiniti or Amazon. I have a tendency to break those plastic things as they get brittle over time. I picked up a whole box for various sizes from Amazon for like $20 which included a few different removal tools. You can also replace the bunch of bolts in the underside cover for pretty cheap. I was actually looking at the infiniti parts website the other day as I am missing one or two and the rest are starting to corrode. They're like $0.75 each or you can just take one to an auto part store or hardware store and replace them likely even cheaper. Better to pay a few bucks now or $100's or $1000's later.