My 2002 s60 is sluggish but yesterday it was running like a dream just sailing effortlessly but today it's back to its old sluggish self...any ideas why?

 

which engine? Any other symptoms and did you check for any stored codes? You may want to try and catch some real time data and if its a turbo you may want to see if its getting the proper boost (ie a wonky boost control valve or a vacuum line issue).

 

Thanx for helping! So ya, it's the 2.4 turbo.to be honest..I just got on this forum about an hour ago & my 02 s60 is having almost every single issue I've read about so far...dies upon startup, sluggish, brake failure lights, Chek engine light, airbag light, hissing or whirring from under hood....geeshe I guess I need help lol

 

So what exactly are "stored codes" & how do I check for them? And just a little while ago, when I started it, it said "0098"??? I think...it might hav had another zero