A faulty coilpack is always a good suspect when wet weather causes rough idle.
Okay... First ill explain what happened. Im driving home, ( 8 hour drive) then it starts raining very hard. I get about four hours into the drive and my car start to sputter..bad. I figure it sucked in water through the cold air intake, there was an extension on it so it was very low. I stopped at auto zone and bought a new cheap filter. That helped..a little. I get it home let it sit and dry out. Symptoms go away. The. 3 days go by and it comes back. I replace the maf, it helps a little still not 100% so i replaced the plugs with the recommended ngk plugs. Still have rough idle when cold, misfire/ shutter at high rpm. Im thinking it may be the coolant temp sensor... Any ideas on what this is? Car ran flawlessly before this. Could it be my coil or wires? I noticed a little bit of the rubber on the wires is cracked where they snap to the plastic trim on the intake manifold. Any body else have or solved this problem before? Its obd1
"It takes alot of money to drive something this shitty"
Crack in the PCV wouldn't really cause running issues because it's not a vacuum leak. But the air it sucks there is unfiltered. I'd definitely fix it.
As for the problem, I agree with others, try replacing the coil pack with a known working unit.
2002.5 Jetta 1.8T - TOTALED (dodging deer)
2002.5 24v GTI - TOTALED (rear-ended by a Jeep)
1992 Corrado SLC - The toy & DD
2012 Golf R - The weekender