Car - 1984 Saab 900 Turbo 16V. 184K miles
Problem - when lifting off the throttle, there is a harsh rattling noise. Only started today, was doing around 75mph in 5th gear on a constant throttle, then lifted slightly. There is a harsh metallic rattling noise that appears when I do this from somewhere in the engine. As I reapply the power, when the engine is in that state "where it's neither under load, or on the overrun" IYKWIM, the noise reappears. It only happens on light throttle, and the engine sounds sweet at any other time. Sounds like a bearing somewhere, but what? Small end? Camshaft? Timing chain slack? I know it's not a big end as I know what they sound like :-(
Thanks! Mike