Hope someone can help me with this.
UK '99 A6 1.8T (150bhp) with 110K miles. Engine runs fine but have noticed
over last few weeks that between gear changes when revs drop to approx.
2000rpm a rattle is heard from the engine. Noise doesn't occur when engine
revs increase, only when decreasing. Does the same thing if sat stationary
and rev engine.
It doesn't sound like a plate/heatshield etc rattling in the engine bay due
to vibration, as I would expect this to vibrate at various rpm whether
increasing revs or decreasing.
Certainly sounds like something in the engine like a chain rattling but
don't know the internals of the engine very well to put my finger on it.
I would be grateful for any advice hopefully to tell my engine is not
terminally ill or if I can expect an expensive trip to the dealer.