**FIXED**
New plugs rotor cap fuel filter, checked vacuum lines gasket under throttle body replaced 2 years ago. Very bad idle and runs terrible when cold after 15-30 minutes of driving gets much better. Before new exhaust installed was fine. This happened all of a sudden. 157k miles.
IT WAS THE FUEL PUMP NOT PROVIDING ADEQUATE PRESSURE. IT FINALLY DIED WHEN I WAS TESTING THE EGR. BANGED ON THE TANK AND IT SPRUNG TO LIFE AND ENGINE STARTED. REPLACED AND ALL PROBELMS GONE.

Bad idle usually means stuck open EGR-- have you checked yours???

No I did not check that as it as still looks new as it was replaced 4 years ago and was thinking they usually last longer than that but maybe a vac line is the cause or debris stuck in the valve. Thanks a lot!