I have a 2001 Pontiac Grand Am with about 160K miles on it. Over the last month or two I have noticed a persistent ticking noise coming from inside the engine compartment. It sounds like it might increase in frequency along with the engine speed. It is loudest when I pull up in a drive-thru or next to another car and roll down my window. It is audible when sitting or while moving. Doesn’t seem to make a difference if the car is hot or cold. I checked the oil and it appears to be full. It sounds like it’s coming directly out of the engine block itself. I get the oil changed every 3,000 miles like clockwork. I’m a grad. student and am worried this is going to cost big bucks. Also, this car is the only way I can see my girlfriend who lives 4 hours away. Any advice would be great! Thanks!
Sounds like it may be an exhaust leak, possibly a leak in the exhaust manifold gasket where the exhaust manifold bolts into the head. Typically a leak like this starts out as a persistent ticking sound and gets louder gradually. Take it to a trusted local mechanic and he should be able to pin down the source.
If you like to tinker, you may be able to find the noise yourself. Take a piece of hose (garden hose, or what have you) and put one end in your ear. With the engine running, move the other end around the engine compartment, starting at the exhaust manifold. Be sure to stay clear of spinning pulleys, belts, and fans.
One thing to check is the serpentine belt. If the ribbed section of the serpentine has started to chunk out, each time that section of the chunked out belt hits a pulley it can cause a ticking noise.
If neither earlier answer helps, it might be a sticking lifter valve. It’s not fatal, I’d just be sure to warm up the engine in freezing temperatures for a few minutes before driving and keep the oil fresh.
But I would not take a Pontiac with 160K on a 4 hour drive. Especially not if the car was making any weird sound at all. My advice is use the car locally and in a safe range - by which I mean you can survive walking home if it breaks down. Just don’t put too much faith in this car.
Maybe rent or borrow a car to pick up up your girlfriend.