Very low idle ?!?!

Hi I drive a 1990 4 door civic ef with a d16a6 and after I changed my clutch my throttle cable shorted out and due to ground wires not put back properly. So I put a throttle cable from a Chrysler 300 on witch surprisingly seems to be pretty much the same as the original. After about 2mo the driving with this setup it now almost wants to putter out at red lights because it's idleing at about 400 450 and quiet..witch is also very surprising my question is is there any other way to change my idle other than the cable because this aftermarket cable doesn't have the adjustment bolts like the original.

 

I would clean the throttle body, try to spray the idle air control valve clean. If that doesn't work there should be a throttle stop set screw on the throttle body you can mess with. People don't like to do this with OE stuff, but with aftermarket throttle bodys and modded setups you almost always have to. So even with stock, when things get old and there may be a bunch of issues, sometimes you just have to mess with it.

 

So after driving for a few days it made my it's way back to the 700-800rpm range l... Now about a week ago somebody stole my catalytic converter and it's loud as can be. I do not have the money to buy a new one for a week or so...and have had to drive it being loud and all... Now at startup It idles at about 2000rpm then levels out at 1500 once it does that it starts jumping up to 2k back down to 1.5k back up....what the heck is going on?!?!!;. Damn thieves