Alright here's the problem. I changed out my intake manifold for the AEBS one. Problem is now my car will not idle under 1500 rpm. I sprayed throttle body cleaner into the throttle body spring ( the gunmetal looking thing) and it idles under 1. so i replaced the throttle body with an ls one. it didint help. is my IAC out? I found some info about checking the iac:

You can test whether your Fast Idle Valve is working by putting your finger at the lower port of the throttle bore, located at 8 o'clock with the throttle body upright. When the engine is cold, you should feel suction and when warmed up (cooling fan comes on), there should be no suction.

can someone help me? is this right? im clueless. sorrie im a newbie