Saturn- po442 code have anything to do with replacing the timing belts

Question

my saturn needed timing belts dealer did the work engine light came back on right after had dealer check code po442 could not find any leak now is suggesting smoke test could this be linked to timing belt fix these are buried in the front on the engine or a defective part i.e. gasket

Answer 1

P0442 Evaporative emission control system leak detected (small leak)

Can it be linked to the timing belt job, No, Before the ECM (engine control module) set a P0442 it would run a set of test it will check the EVAP vent circuits, It would also have to run and pass a P0455 ( large leak) and a EVAP system flow. What you may just have would be a faulty fuel cap  only.