My aveo will start but it will not idle,but weird thing is it doesn't do it all the time.other times it will start and idle normally but when you drive and stop it doesn't idle.the icv has been changed but stiil it is doing the same.any 1 has any other ideas what it can be.also I have a elm327 but no fault code is coming up.even the intake has a new intake gasket set fitted.