I own a 2012 s60 five cylinder turbo and the dash had the check engine light on for about a week before I could get the car to the shop. I had the OBD2 read at O'Riely's and it said that I had misfires on cylinders 1,2&5 and random misfires. I replaced all of the cylindrts and the misfires continued. The car after driving it for two days has gone into safe mode with the "reduced engine performance" message on and the car won't start. Should I replace the coils and get new spark plugs? Heeeelp

 

You should start with not driving the car any further. Driving with multiple misfires is damaging to the engine, especially over several days. Driving it long enough will be catastrophic. I suggest getting the car properly diagnosed by a shop with a scanner that is familiar with volvos or at least has a good reputation and equipment/scanner to communicate with each module in the car.

Not sure what you mean by "replaced all the cylinders"

 

+1 on getting a pro diagnosis. Don't waste your money replacing all the coils - they are individual components which would not fail all at once. Generally spark plugs should be replaced every 60K miles so again not a likely cause but removing and inspecting plugs can give you some clues. The most likely cause of a happy meal of misfires is fuel mixture which can be caused by intake air leaks, fuel pressure issues or a sensor being off (such as the engine coolant temp sensor). In rarer cases the valve timing could have jumped a notch or two (particularly if the timing belt was not serviced on time- your car is due at 10 years/120K miles). Other possible causes like a head gasket issue would present other symptoms like coolant loss or too much pressure in the system or the dreaded oil milkshake.

 

Thanks for all your advice. I just so happened to talk to my mechanic today and he said he would diagnose it for ree whew! I just hope nothing really serious is wrong with my little muffin.