99 cutlass is running rough in idle and while driving

Just bought a used 99 cutlass in the last few months and about a month ago the check engine light has been coming on intermittently. Just today the light started blinking and the car started shuddering and running very rough. Took it into a shop and had the code read and the mechanic said that the # 3 cylinder is not firing in time. Is there a way to reset a computer chip or does it need something simple like a tune-up? On top of this when I took it in for an oil change the mechanic said that there was oil in the anti-freeze resevoir. Could these problems be related?

Just bought a used 99 cutlass in the last few months and about a month ago the check engine light has been coming on intermittently. Just today the light started blinking and the car started shuddering and running very rough. Took it into a shop and had the code read and the mechanic said that the # 3 cylinder is not firing in time. Is there a way to reset a computer chip or does it need something simple like a tune-up? On top of this when I took it in for an oil change the mechanic said that there was oil in the anti-freeze resevoir. Could these problems be related?

oh yeah they can and probibly r. either intake or head gasket

Check the Malibu forum for the intake manifold gaskets and if you choose to go that route, choose the Fel-Pro Problem Solver. Don't accept that old GM set because it will fail again.