Chevrolet Repair: 99 Cavalier Idling Rough, chev cavalier, ac delco

Question
Hi Steve,

My 1999 Chev Cavalier started to idle roughly yesterday and the check engine light came on blinking.  I had corrosion on the ignition coil module under plug 1 and 4.  I cleaned them off but the car still is idling rough.  The plugs were changed last summer (AC Delco) so I am unsure what I need to do.  Would changing the ignition coil module remedy this problem?  Can I change it myself?

Answer
There are several things that can cause that condition and the last thing you really want to do is change parts without knowing what is causing the problem, since you do have a check engine light my recommendation would be to have a diagnostic check performed to read that code and see what is causing the problem