Smell a burning, but no smoke

I am a single mom and don’t know much about cars. I have a 99 Mercedes e-320 and I started smelling a burning, but when I opened the hood, there wasn’t any smoke. What could it be and is it still safe to drive?

From a distance, nobody could possibly tell you exactly what the problem might be, but I can give you two possibilities:

There might be a plastic bag that got stuck on the undercarriage of the car, and is being melted by the heat of the exhaust.
or
There could be a slight oil leak that is dripping onto the exhaust manifold.

I’m sure that other forum members can provide additional possibilities, but only a mechanic who can examine the car will be able to accurately diagnose the source of the smell.

You need to have the vehicle looked at by an independent mechanic. That smell could me something as simple as a stuck brake or as serious as shorted wires that could potentially cause a fire. See a mechanic now.

Thank you both, I will get it to the mechanic right away.

As said above, this requires a shop’s inspection. Most likely something to do with a high current circuit. If it occurs in the daytime when the headlights are off, my first suspicion is the fuel pump relay. I had a VW Rabbit years ago with this symptom and it was caused by a failure in the thing the fuel pump relay plugged into, the fuel pump relay plate. It turned into a big mess b/c the dealership made a mistake when they fixed it, which blew the new fuel pump relay too. And when the fuel pump relay goes, the car stops. Which of course occurred on the freeway. During a snow storm.

From my limited exposure to that engine I’d say the valve covers are probably leaking.

How long have u owned this car?

I have owned the car for 19 mos