I have this "groan" from the engine that seems to only occur when the weather gets cool and humid. What the heck is it? I have a '97 SE 5spd with 63K miles. It's not the clutch, as it does it when the clutch is in or out. Happens til it warms up, after a mile it's gone.

 

Hey Curt, my car is sluggish too. Is is a Minneapolis problem? It usually happens on my way back home after work. I also thought the weather was the problem and I cleaned my filter on my warpspeed CAI and check my plugs. I also cleaned the throttle body and changed the the PCV valve (both before the sluggish problem). I also questioned the fuel I used the other day. So I am going to get some injectors cleaner and fill-up my tank with some 92 octane. Maybe it will help...
Kajeno