Bru's question is key to resolving this issue. You can get hundreds or even thousands of questions or suggestions about replacing particular components, but until you get some DETAIL about why that check engine light is going on, you're shooting in the dark.

Your car's computer actually stores some information about what it thinks is wrong, and you can retrieve this information by hooking up a code reader tool. That is what Bru is referring to when he asks about On Board Diagnostics (OBD). You'll usually here it referred to as version two (OBDII) of this computer/code reader interface.

Chances are good that the dealer recorded the prior error codes on the service invoice. Get that information and report back here.



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Jim Rothe, '99 S70 T5M,
http://www.jimrothe.com/volvo/index.html