finally took off the etm, it turn out to be the sensor strip inside.it had no scratches but it was faded and could see though it, i fitted a after market contactless sensor it removed the problem, along with the engine light i followed a youtube video on how to do bit of a mission but it was pretty ...

thanks I have a new throttle body sensor coming ,will clean throttle body then .Will post the outcome cheers

hi i have a 2000 volvo s80 t6 2.8 i got it 3 months after the the previous owner have a new engine installed i have done about 8000 km in it ,3 months after it started to rev back and forth from 1700 rpm at 80 kmh then back to 1500 rpm. then at a 100 kmh it would rev back and forth from 2000 rpm to ...