2000 Dodge Neon clacking noise at low rpm after releasing gas pedal. Around the 2000 rpm range letting off the gas produces a clacking noise. I have listened to the engine with a long screwdriver at idle and revving. The noise is not always present in this condition. Although when it has come up it seams to coming from behind the engine. Does not seem to be valves, connecting rod or main bearings etc… Only at low rpm 1200 thru 2000 rpm WHEN releasing the throttle. Clacking seams to be timed with the crankshaft as it reduces the sound as the engine reduces rpm, not at the speed of the cams. Sounds fine at idle, going through gears and at freeway rpm’s.
Could you just have a loose heat shield that the two halves are tapping together