You two.. change your spark plugs, air filter, and do a full server. Whilst you've got the air intake taken apart, spray wd40 into the trottle body (open the valve and spray in)
If that doesn't help... buy some silicon and cover your coilpacks in it. This helped my misfiring problem.
Run on 98, I fully recommend vpower. I fall in love with my car every time I've switched back to the petrol.