This phase II trial studies how well carboplatin and etoposide with or without oblimersen sodium works in treating patients with extensive stage small cell lung cancer. Drugs used in chemotherapy, such as carboplatin and etoposide, work in different ways to stop the growth of tumor cells, either by killing the cells or by stopping them from dividing. Biological therapies, such as oblimersen sodium, may stimulate the immune system in different ways and stop cancer cells from growing. Giving carboplatin and etoposide together with oblimersen sodium may kill not tumor cells