Why would a 1997 Dodge Caravan engine make tapping-ticking noise that went away after warming up but now is constant and seems to come from the top of engine?

It's difficult to diagnose a specific engine problem without being able to inspect it directly. However, based on your description, here are some common possibilities for a 1997 Dodge Caravan engine making tapping/ticking noises that get worse over time:

Possible Causes:

* Lifter Tick: This is a common issue in older engines, particularly with high mileage. Lifters are responsible for providing oil pressure to the camshaft. If they become worn or clogged, they can create a tapping noise that gets louder when the engine is cold. This noise may lessen when the engine warms up as the oil becomes thinner and flows more easily.

* Valve Train Issues: This could include worn rocker arms, valve guides, or valve springs. These parts are responsible for opening and closing the valves, and wear can lead to a tapping noise that worsens over time.

* Timing Chain/Belt Issues: A worn or loose timing chain/belt can create a rhythmic tapping noise. If the chain/belt is about to break, the noise will likely become significantly louder and may be accompanied by other symptoms like misfiring or stalling.

* Loose Engine Components: A loose bolt or other fastener on an engine component can cause a tapping noise.

* Fuel Injector Noise: While less common, worn or faulty fuel injectors can sometimes produce a ticking or tapping noise.

What to do:

1. Check your oil level: Low oil levels can cause lifter tick, so it's essential to check and ensure the oil is topped up to the correct level.

2. Listen carefully: Try to identify the location of the noise. If you can pinpoint it, it might help narrow down the issue.

3. Get a mechanic's opinion: Since you've described a worsening noise, it's crucial to have a mechanic diagnose the problem. They can use a stethoscope and other tools to pinpoint the source of the noise and recommend the appropriate repairs.

Important Notes:

* A tapping noise that is constant and gets worse over time is not something to ignore. It could indicate a serious problem that could lead to engine damage if left unaddressed.

* Do not attempt to diagnose or repair the issue yourself unless you are a qualified mechanic. Improper repairs can worsen the problem or even cause further damage.

A mechanic will be able to diagnose the issue accurately and recommend the best course of action.