idle and start issue

I have a 93 2.3L mustang and have been experiencing some issues with it lately. first its hard to start sometimes. It will turnover a few times stop and continue to turnover with no start ( for some reason i have found holding the throttle will make it start). secondly is the idle. when idling if I tap the throttle the engine will bog down slightly and the rpm will reduce to 400 revolutions are so, then idle at roughly 1500 and slowly reduce to 1000ish.
i have cleaned the throttle body,icv,egr,and upper intake
new ignition module and spark plug wires.
also i have a ranger header on it, so there is no pipe feeding the egr valve and have 17 LB injectors.
help greatly appreciated!