I have a 1988 VW scirocco with 39,000+ miles with a rattle that seems to be coming from the engine area. Here’s what I’ve observed…while driving down the road when I let off the gas pedal, there’s a rattle that sounds like a loose part inside the engine. It happens when going down hill and sometimes on flat areas, not while going up hills. Any thoughts??? The car is a manual trans. I recently had the gaskets replaced and all fluids flushed as well as a tune-up.
Perry
Have you checked the motor mounts?
No, Motor mounts…really?
My '83 GTI needed them, it’s pretty common. Do you have a good VW mechanic?
Of course it could be something else, but that’s the first thing that came to my mind.
Could be a rod or maybe piston slap?
The Scirocco is a front wheel drive, right? Check the exhaust system. There are metal shields, and the flex pipe may also be loose. That would show up more when not under power, but I would also expect an increase in exhaust volume.
There used to be a metal shroud over the manifold that would help the engine warm up by sucking warmer air from the area surrounding the manifold into the carb. Unless I’m completely off base, they used to rust to the mount bolts, and would shear the metal and rattle. Pretty difficult to see, but if you grabbed it (engine cold, of course), you could move it around and see the cracks around the mount bolts.
Very hard to tell. A mechanic will find it quick likely.
It could simply be a loose exhaust component or shield. Or your timing belt tensioner going. Or somewhere between.