i have a 2000 volvo s70 that is acting really strange for the last 2 weeks. it vibrates alot and is very sluggish at acceleration and doesnt accelerate as good and fast as it used to. autozone hooked up the diagnostic tool and the car gave off errors po303 p1171 and p1174. what do these mean and which parts should i replace to fix the problem. please help.thanks

 

Well you've got a misfire in cyl #3; do you have any diagnostic skills or tools, or do cars befuddle you?

Have you checked for compression, or spark on cyl #3? Since this is your 1st post a bit more background might be helpful.

BTW: OBD2 codes help point someone who understands automotive systems where a potential problem might be; they don't say ".. replace part X for code Y.."