Noisy 4.0L engine.

[trcoa1]

I have a 2001 Sport Trac with 187,000 miles. The engine has a clatter sound when idling that seems to be coming from the front of the engine. When accelerating the noise becomes louder. At 30 mph the noise sounds more like valve pinging. It stops when I let off the gas. I've changed the intake manifold gaskets (top and bottom) and nothing changed. It has been a long time since the last tune-up. Could this be something as simple as needing new sparkplugs?
I checked the forum on timing chains and nothing was mentioned about noise while idling.

 

[2000StreetRod]

Bad bearing?

It could be a bad bearing on the water pump, idler pulley, tensioner pulley or power steering pump. The most common failure is the water pump. An easy way to tell for sure is to disconnect the serpentine belt when the engine is cold. Start the engine and listen for the clatter. If there's no clatter then the source is one of the accessories driven by the belt. If you still hear the clatter, it's coming from the engine internals or external vibration such as the exhaust pipes. The engine will not overheat if you run it for a minute without the serpentine belt spinning the water pump.

 

[BrooklynBay]

Welcome to this forum! I've moved your thread into the 2001-2005 Sport Trac section.

 

[Pheonixx77]

this may sound stupid, but check your catalytic converter heat shields. Ford is notorious for bad welding in that area. the rattling they make can sound like anything from a tranny gone bad to a broken connecting rod. my ranger, explorer and my f150 had problems with bad welds on heat shields.