So about a month or so ago my gauges started going up and down erratically upon starting my 99 silverado 5.3. There's also an occasionally burning smell and the battery light comes on (the battery light comes on every time though not just with the burning smell, same for the flickering gauges.). Once I get on the road everything's fine though, the battery light isn't due to alternator or my battery because I've changed those out recently. Does anyone have any ideas of what this might be?

if you need any more info lmk, also I have an oil leak and that could possibly be the burning smell but uts very brief, so I doubt it.
Thanks

 

Is the burning smell inside the passenger compartment, next to the Silverado, or both? If it's interior only and smells somewhat acrid, then you likely have a couple of wires shorting out.

As far as the erratic gauges go, sounds like there is a bad ground to the instrument panel.