Idel's is rough only some time, its not rough all the time,

i have seen many strange things happen with the distrib cabs on these

Check egr valve, gasket, vacuum line. vacuum leak or sounds like to me.

Check the intake hose to make sure that it doesn't have a whole in it also check the air box that the filter goes in also. Mine was idling rough also and we found a whole in the filter box and the intake hose had a whole in it. Hope this helps.

test for spark at the 2 plugs

you might want to replace the plug end. I had a 99 neon with the same ploblem changed the sensor but the plug was shorted, changed that and it run great ever since.

sounds like you may have a problem with your Idle air control valve, located on the throttle body. this is what controls the idle when coming to a stop or stopped and turning corners or basically when your foot is not on the gas pedal

Remove one of the spark plugs and see if it is wet with gas.
Let me know.
Regards,

As a former Audi technician, I can pretty much guarantee the coil packs are your problem.

I would check the exhaust pipe a little closewr. White smoke can also mean a blown head gasket. Check the tail pipe to see if moisture is present. Also check coolant level. A blown head gasket can also cause related problems.

Bill

The "check engine" light will "light" when there is a malfunction in the engine management system. The fault code is then stored in the computer. The computer must be scanned to retrieve these stored faults to pinpoint the malfunctioning component. We recommend buying your own scanner and doing it yourself. With a pocket scanner you can check for fault codes to find out why the light came on in the first place. You can clear your cars trouble codes after you replace the malfunctioning sensors.