[somick]

You need to know what the code is.

There is no sence to not trust your mechanic but it sounds weird when he tells you to keep driving.

Check engine light tells you - there is something wrong, I need help!!!

From what I have read, cars with that age and milage have problems with oxygen sensor. If you keep drivign with the bad sensor you will hurt your catalytic converter and it will cost you a lot more to fix your car.

Start with reading your codes. Autozone will do it for free.

Good luck,

Sam