What could be causing service engine light to illuminate?

usually comes on when maintenance is due (i.e. 30,000 miles) will try to inspect and sell you things to put the maintenance items tended to (i.e. light bulbs, wipers coolant and waterpump check) it is a numbers game...they want you to repack your wheel bearings and change your timing belt~

HoHo- the judge is cynical today- but truthfully, there is good cause for cynicism- service departments need to make money- but a good garage will just you a scanner and see if the computer will tell them what is causing your light to come on- then fix it for you- then the first thing you do is go to DISNEYLAND!!!! flowers and little birds singing, and everyone lives happily ever after

some of these folks really get the most of their cars....pushing 250,000 miles....um..okay what's the normal maintenance for a car like this? all we can do is inspect the wear items, not like tryin' to "put it back to factory" like they'll do with a 30,000 Mile maintenance...but seriously doing a bit of inspecting...

I don't believe the car has had any maintenance up until being in my hands and I bought it at 150k. I suspected oil change of course but wanted to be sure Volvo (as I'm learning is a tricky make) doesn't have some ulterior meaning behind that light.

not that your nose has a spectral anylizer in it, like mine does, but can you smell the exhaust and tell me does it smell oily, carboney, coolant- ey or just plain white smoke?...see lack of maintenance will cause the motor to burn oil...of course a snapped timing belt is an issue on your Volvo s40 interference engine...so we don't need to go there, but you could start lookin' for trouble...not that it's a good idea to go lookin' for trouble but perhaps the light coming on is tryin' to tell us something important like the MAF sensor isn't working properly (like my 240 used to) the self-diagnostics on an old volvo had you reading a series of flashing lights when you turned the ignition on...if there's an OBD-II port let's connect to it...and get a printout of the results...post them here and be given more options for service~

Get a new timing belt and water pump for continued SERVICE...soon~ was going to assert that yours had a non-interference situation like the 240s do but the S40 1.9 liter model HAS an INTERFERENCE belt...change it or assured destruction is going to happen....worry, please do something with it.~

Actually was told by dealership that timing belt is cracked and in need of replacing. Any relation in poor performance? Or just extremely dangerous?

SUICIDE~

'couple of tools and you could do the job yourself...the tensioner is going to be worn...that's why you might notice that tensioner pulley in that kit...If you're any good with tools and not intimidated, do the job yourself...on a difficulty level of 1-10 would put this timing belt at around 5 difficulty level...will take about four hours time even with an experienced repair person....a bit of disassembly...draining of coolant and disposing of that coolant properly (in empty milk jugs to take back to the auto parts store)...do not overtorque your fasteners...a temptation for a newbie~

Point taken :-/ Thank you!

Appreciate the advice, but would be better off taking sledgehammer to her than touching her with my inexperienced hands. Been told Volvo's are no place for an amateur anyway. More interested in trying to pinpoint problem, figure out what parts I need & paying someone else (not a million dollar dealership) to give it their best shot.

nice photo ksnow...it's always nice to know who we are talkin' to~ took me a lot of courage to put my mug up there, but when was issued the CarGurus hat felt somehow obligated to represent~

find someone you can trust, who isn't rich~ $60/hour is a fair price for a good mechanic....if they don't drink beer on the job and take "smoke breaks" all the time punchin' a four hour job out to a ten hour job~

You've got a sledgehammer?...ooooo I'd like to see what you do with this thing.~

Felt a little more personal. I'm nervous having anyone besides a Volvo specialist touch it due to the horror stories I've been reading. However, I'm taking it to the same mechanic who's worked on my Dodge & Cadillac. I figure it can't be too different... then again, could be as different as a FOREIGN country!

Had a real easy time with the Volvos because at the time you could not mess up a timing belt job and ruin the motor (my first timing belt...a honda) felt sorry for the kid...the boss was an ass but covered for me...embarrassingly...only reason I was off the hook was 'cause his radiator leaked...still wanted to fix his old Honda....but a Volvo...you CANNOT mess up a timing belt job....but alas the S40 1.9 L. engine is a horse of a different color and you CAN destroy the engine by installing the timing belt incorrectly....one of the biggest fears on my MINI cooper until I learned that the R50 engine has a timing chain not like the R52 (cooper S) which has got a belt~ at this stage of my life will pay my beloved MIKE at Berkeley Motor Works BMW (clever)~ got MS am supposed to do nothing....but I never listen to orders and distrust the medical profession entirely~

you could put a personal mail to Lars Cats not a Volvo expert, but a hell of a nice guy....needs to get out there more~....sounds Swedish at any rate~