Help, Advice and DIY Tutorials on Volvo's P80 platform cars -- Volvo's 1990s "bread and butter" cars -- powered by the ubiquitous and durable Volvo inline 5-cylinder engine.
Told you
The parts guy at my local volvo dealer immediately yelled temperature sensor when he heard engine revving by itself.
I swapped it 1,5 year ago. And never had the problem again.