I am to the whole volvo thing so don't pick on me to much. My service engine light came on and I was almost due for an oil change so I went ahead and changed it. I used shell 10w30 and a genuine Volvo filter. The service light didn't go off but I didn't figure it was a big deal.Everything went normal until I drove it for about a mile or so. The check engine light started flashing and the motor started running with a strong miss. I have had the same problem in the past while road racing hondas and it usually turned out to be small ignition issues but in this case the car is a little more advanced and the problem didn't happen until I changed the oil. Any help would be great or maybe evan just some random opinions.

 

The 'Service Engine Light' has to be reset to make it go off.

To do this on the S40:
Switch ignition OFF.
Press and hold the reset button for the trip meter.
Switch ignition ON.
Keep the button depressed until the Service Engine Light flashes (approx 10 seconds).
Release the button within 4 seconds. There will be an audible signal when the reset is complete and the light will go out.
If the reset button is not released within 4 seconds the service indicator will not be reset but the light will stop flashing.

Give that a try and see if it resolves the running problem. If not then let us know.

 

Okay, so i reset the service light and on my way to get the check engine light checked it went off. I had it checked anyway and it was a code for cylinder 3 misfire. It seems to be running fine now. I have driven it about 30 miles in town with no extra lights. Whatcha think?

 

Did you spill oil during the oil change?