Hi I have a 99 Saturn SL2. Back in June I was driving normal, the car was normal, or what I thought was normal (Car had been idling high at start up but would eventually go to normal, and there was a vibration I could feel in the steering wheel.) Made a stop, took off and car had issue going up a small hill. Made another stop, drove at 55 or so started to notice car making weird clack/knock/whir type sound when pushing the gas pedal. So i went home and googled my spark plugs. This told me I had put the wrong ones in 3 years ago and likely it was just catching up to me now. So... I ordered NGK's put them in and changed the wires as well... idle is back to nearly back to normal at start up, there's vibration and the car still makes the put put at idle or slow speeds and the clack/knock/whir thing every time I accelerate. I'm terrible at describing sounds so I included some mp3 files.

Thanks!
Ps- Car not throwing codes, shows no misfires.

 

Sounds like a rod is going.

 

That second recording is “ I have run low on engine oil and need a new engine noise” I would discontinue driving it and look for another car. It will go bang and leave you walking. Sorry.