Mike,

Thanks for the info, the car is a 1997 GLT 2.5 Litre Turbo with over 100K miles the O2 sensors are original parts.

My check engine light has come on and gone off the next day two times recently. since the light has gone off i have not checked the codes in the ecu. i do have a code reader.

The car a has also had slightly decreased mileage recently so i changed the spark plugs last weekend with some new bosch double platinum's/air filter and the car runs better but still has some problems it feels like it is surging or missing sometimes on the highway when i floor it to pass another car but besides that runs OK. The exhaust has at times looked like the car is running rich so the 02 sensors may be indeed be going out.

is it worth cleaning them, i have heard mixed reviews on this.
are the bosch 02 sensors available at local autoparts stores for our cars or do they have to come from the dealer?

thanks

Dan