Q: How can you tell if the timing chain is causing a noise only when the car is cold? 2004 Nissan Maxima

Hello - more than likely, the noise you hear when the engine is cold is the camshaft timing actuators. These components utilize engine oil pressure to operate. The engine oil drains off overnight, and it takes a few seconds to refill and become cushioned by oil pressure. While this happens - all in a few seconds - there can be a light clatter from the timing components. This is also true of the timing chain tensioner, which uses engine oil pressure to keep everything tight and operating smoothly. If you are getting problem codes that set off the Check Engine light, or believe the noise has become excessive, I recommend an engine noise inspection performed by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, give you an accurate assessment of damage and cost estimate for repairs.