1993 Toyota Truck sputters when cold

The engine is a 22R-E and has 163,000 miles. I changed the plugs and wires in the spring but didn't have any problems until cold fall days. The engine starts and runs fine for about 2-3 minutes but a couple of times did it as soon as the engine started. The the idle drops and the engine sputters for about 30-60 seconds. If I am driving when it starts to sputter I can tell that it did it but it doesn't really affect how it drives unles I have to stop and go or if I step on the gas while driving. In either of those situations the engine nearly dies (acutally died at a stop light once.) If I stop while it is sputtering the exaust smells like rotten eggs. It does it only when the engine is cold but I have noticed it doing it when the engine is warm but not hot. Once the engine is hot it doesn't do it at all. I have not changed anything on it other than the plugs and wires nor done anything to fix the problem other than making sure there are no cracked vacuum hoses. Any help would be appreciated.