With a clutch it could be a lot of things. Since it doesn’t engage, most likely a bad slave cylinder or throw out bearing. Look for slave cylinder fluid leaks on the transmission case near the throw out arm.

Also, listen when pushing on the clutch for noise. Noise and difficulty engaging indicate a worn throw out bearing. More of a long shot is a worn out clutch pressure plate or disc.

The throw bearing always requires transmission removal to replace. I am not familiar with the slave cylinder location in your car. Usually it also requires transmission removal to access. If you need to remove the transmission it then makes sense to do a full clutch overhaul. Throw out bearing, slave cylinder, pressure plate, clutch disc and pilot bearing.

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Will I buy another Volvo??? We'll see....