Occasionally there is a squeak (around 40 seconds) coming from the engine area when I start the car. What could be causing this?
The noise is coming from the serpentine belt. The belt is most likely loose or glazed over from needing to be replaced. Check the belts for tightness by twisting it between your finger and thumb and it will be hard to turn sideways if it is tight enough.
Also, look at the belt for shinning surfaces or missing grooves. If any problems are noted, then the belt should be replaced and all pulleys checked for any problems and replaced at the same time.
A good place to start would be to have a mechanic diagnose the engine squeak and recommend the best path to repair.