You can drive without it, but I would get one as soon as possible.
It''s a lot safer and better for the engine and transmission to have the undercover. A lot of newer cars have undercovers for a reason.
Here's why:
if something kicks up into the engine bay while youre going down the road, and god forbid if it hits the turbo oil lines or whatever other sensitive parts under the hood, and causes a major "quick oil drain" while you're going down the road, you will wish you had the undercover. Also, if you run over something, the cover will take the impact, not the engine.
The other reason why it's beneficial to have the undercover is aerodynamics. I'm not only talking about fuel economy, I'm also gonna talk about air flow and cooling. Often, people think not having the under cover will improve engine bay air flow and cooling, but that's not true. The undercover will make the air flow smoothly through the engine bay. Air will come in from the grill, through the radiator, flow through the engine bay, and smoothly exit out of the back of the under cover. Smoother air flow will also improve fuel economy during high speed driving. Without the under cover, the air flow will be disrupted, and I don't know why anybody would want disrupted air flow.
There's a reason why the engineers decided to spend money and design a under cover for our cars. There's is a purpose behind the covers.
If I were you, I would try to find a used undercover, and I would slap it under the car.
I personally am not really worried about the air flow aspect, I'm more worried about something potentially impacting the engine, instead of the under cover. I've had multiple instances of something hitting the undercover while I was going down the interstate. My undercover is banged up and scratched up on my 2010 Taurus sho. I'm glad the undercover is banged up, instead of my engine.
