bad idle problem :(

Im just wondering if anyone else has ever experinced this kind of idle problem. It basically is 3 things that are not normal with it
1. Driving in lets say 2nd i shift into neutral and idle will only lower to 1600rpm or so than when i come to about a dead stop it drops to 1k rpm.
2. First 3 gears seem to actually make rpms jump when clutch gets pushed in and this is with absolutley no throttle.
3. Last but not least is when i go to start my car idle goes up to 1700 than slowly drops to 0/stalls if no throttle is given.

Im just wonderin if this might be dirty tb or maf? Thx for your time u guys this problem has been with me since like 2 months after i bought the car but i can atleast say i killed a 01 prelude with 75 shot intake/exhaust

THx again you guys

yeah i checked the vac guess its gotta be sumthin else :/ do you thing the clutch might be slipping if my idle jumps like that from just pushing it in? thx again for your help hissin

ill have to check that havent had the time but yeah im basically stock only time i have messed with tb or maf was to remove it to put the el shortys on. I also talked to a mechanic where i work he said its probably that. Thx for ur help u guys least i know now this isnt tranny/clutch related