Ticking

Hello, I have a 2004 Chevy cavalier with 133,000 miles. For the last week I have been hearing a ticking noise - seems to be coming from inside the dash board on the passengers side (glove compartment). The ticking noise begins when the engine starts up and stops when the engine stops, so the noise is continuous while the engine is running. The car runs well, no loss in power, nothing out of the ordinary, with the exception of the noise. I opened the hood and listen - the sound seems to come from inside the firewall.
Hoping maybe you might have some idea.
Thank you

Could be the hvac fan as it goes around. It is on low speed all the time. Does the ticking change if you speed the heater fan up at all? Otherwise it could one of the heater controls I suppose but you’re probably just going to have to have someone listen to it.

If the origin is inside the passenger compartment, as @Bing says, likely associated with the heating/venting/AC system. Turn those things on and off, adjust the temp, adjust the fan speeds, and see if it makes any difference. Could provide a clue.

If the sound source is inside the passenger compart, it is important you have the timing belt checked asap – assuming you have a belt rather than a chain – especially if it is past due.

If inside the engine compart I meant to say, check timing belt … sorry for mis-typing.

Does it change with engine speed? If so, definitely check the timing belt, if not, change the heater fan speed, and if it changes with that, then it’s probably something stuck in the fan. That happened in my car a few months ago, and while it is annoying, it would be too expensive to take apart the dash just to fix it, so I lived with it and it went away eventually.

In addition to changing the fan speed, or turning it off, change the vent options between floor, dash and windshield to see if one of those positions stops the noise.