Hi, first time on the forum....

Wondered if anyone could help.... I have an Astra H (59 plate) diesel estate with 35k on the clock. Recently I've noticed a couple of noises which I wondered if they were linked?

Firstly when the engine stops, i hear what sounds like an electronic 4 or 5 clicks/knocks from the engine every time? Does anyone know what this could be? Could the noise be the alternator or something?

Secondly the engine has started to start making a louder sound when traveling at 70 ish mph. If you come off the accelerator it sounds like the engine revs slightly for a bit longer. The noise is there when the accelerator is on too but comes and goes intermittently. I know it's vague but wondered if anyone had any ideas...I know it sounds a bit like a clutch but I've had one go before and it doesn’t seem the same, it's not over revving etc

Thanks

Dave