i didnt install it and I have just picked up the car so havent gone back to shop yet. What could have caused that? should i be concerned . .....i read some threads about people with rough idle who fixed problem by cleaning throttle body and idel air control valve. I dont want to have to replace that valve hella expesnive part 180 bucks so anyone willing to give step by step instructions PLEASE

 

if it started after you got the car back, then it's a problem the shop caused. take it back to them and make them fix it.