hey i own a Volvo s 80 and it is running fine but sometimes when i run on 40 to 60 mph it the rpm starts to go crazy like up and down up and down , also when i drive over 120 i feel a shake comimg from th eengine what can it be ???? any tips , i already changed my spark plugs and my fuel filter ,and oo forgot to tell you guys it's a 2002 2.4 5cyl car and thx
ganganputput
Favorite Answer
engine shake comingfromdriving above 120mph could be due to loose or old engine mountings.get a workshopto checkthem out.
The engine revving up and down between 40-60 mph sounds like some problem with the cars electronics, or the electronic part of the auto gearbox(if you have an auto version) see if you canfind a dealer with a volvo compatible diagnostic computer, get them tohook upyour car and run it through a diagnostics. you mentioned that it is an intermittent problem. probably more likely tobemechanical, innature, some part partly wornout,so gives such problems.
hobbabob
t shirt guy has a good point. if the torque mount is bad the wiring harness will over-flex with the engine and after a while will break the wires inside. resulting all kinds of intermittent symptoms as well as strange viberations
Anonymous
Could be wheels need to be balanced, broken engine mount and a wiring issue with the tachometer.
Somethingtotry
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