I have a 2004 XC90, regularly serviced, with Check engine light coming on. It has 96,000 miles and I am a bit overdue on oil change. Could this be the source of the check engine light coming on?

 

Could be anything from a part in the emissions control system to a loose fuel cap. I have never seen a Volvo give you the light due to oil - it will throw up a service reminder in the message window for that.

 

you need to get the code scanned. it could be 1000 things. oil should not set off the MIL (malfunction indicator light aka check engine). autozone or other shops will scan codes for free. loose gas cap is common cause. you can also buy an OBD 2 code scanner for $60 or so.

 

I too have an '04 XC90 and Auto Zone just gave me two codes.

P0299 which says Turbo/Super Charger Underboost
P0154 which says Heated Oxygen Senson - Bank 2 Sensor 1 (HO2S21) sensor circuit no activity detected.

Can someone tell me what I need to look for? I am 200 miles away from the Volvo dealer/service department where I purchased it so not easy to take in if there can be a quick fix.

 

My 2006 XC90 V8 has had a good relyability record so far but today it showed an engine alarm, but no message. The owner's manual says "Fault in car's emissions system". Does anyone have any suggestions about what is the problem? Driving it to the repair shop (about 20 miles) with the alarm on would damage the engine?