Volvo: S80 Emission System/Check Engine, oxygen sensors, emission system

Question
Over the last 6 months, our 2000 S80 Emission System and Check Engine alarm lights have stayed on.....not a new event, I might add.

After the car completely quit on a trip, we had the fuel control module replaced, as well as two oxygen sensors that we were promised would address the emission and check engine alarms. Filling-up w/gas immediately after the "repair", the same alarms reappeared. AND, since this latest fix, our gas mileage has deteriorated significantly.  We've spent almost $2,000 just to address these alarm indicators.

Any ideas before we return to the shop?

Your input is GREATLY appreciated!

Answer
Hello! I'm not sure how anyone can promise that the ck. engine or emmisiions light will never come on. There are far too many reasons to list why those warning lights come on. It is best to have the car checked out again. Try another dealer if you are unhappy. It really needs to be checked by someone who knows what they are doing.

Jimmy