running rough

It could be a fuel issue. There is probably some water in the tank. You can get a can of dry gas/heet from the parts shop and put it in and put some premium gas in. That should help you to burn out the water.

Those cars also have a habit of coils going bad. You should probably get a spark tester and check the sparks coming out of the coils. Here is the tester that I use: https://www.amazon.com/Lisle-20610-Inline-Spark-Tester/dp/B0002STSC6/ref=sr_1_3?ie=UTF8&qid=1501325755&sr=8-3&keywords=spark+tester - They do sell it at AutoZone for about $15.00. Check all six cylinders. If you see one that is weaker than the others, you need a coil. Here is a link to that: https://www.amazon.com/Ignition-Cadillac-Chevrolet-Oldsmobile-Compatible/dp/B071X7D2NR/ref=sr_1_1?s=automotive&ie=UTF8&qid=1519991195&vehicle=1995-47-432-------------0&sr=1-1&ymm=1995%3Achevrolet%3Acamaro&keywords=95+camaro+coil&dpID=41kQew%252BUrEL&preST=_SX300_QL70_&dpSrc=srch

Start there and let us know what you find.

2003 Chevrolet impala does not stay running on cold start low idle.

Beaner - Go ahead and start a new thread on that at 2carpros.com and someone will be glad to try and work it out with you. Taking a shot in the dark, I would check the IAC motor (Idle Air Control). This helps control the air flow going into the engine. If the motor is bad, it is stuck in whatever the last position it was in when it was working, which is probably the position needed for when the engine is warm. Thus, the engine is not getting the right amount of air when it is cold and is struggling to idle.