Cold/Rain engine troubles

[bp057]

So today is the first time since I bought my 91 that the check engine light came on on the freeway. Im thinking it may be the AEM intake getting a little mist or water since the headlights are up. Also, last night without rain, if I hit the throttle real quick rpm would go up, then dip to about 200 then settle back around 700. Any ideas before I throw money at autobacs to fix?
Thanks!

[wootwoot]

Possibly could be coil packs arcing or spark plug wires

[Sil Beer S13]

Change your plugs,wires,cap and rotor.

[bp057]

Im running denso's and 10mm wires, cap and rotor Ill swap, could be condensation in there I suppose. thx for the ideas

[papershot]

you should check to see what the ECU code is before you buy anything.