1996 Ford Thunderbird 4.6 Irratic Idle

I've owned this car 6 yrs., has a 4.6, looking at almost every inch on the topside replaced several bad vacuum lines, idle module near the intake, complete tune-up, oil change. Recently had the crank sensor replaced, following morning tried starting, idle was up and down, almost stalling, thinking a vacuum line is cracked, anyone had this issue before...with the car being 20 yrs old or so 230k miles and normally smooth, no problems until now..

I have a 96 ford tbird 4.6 with irratic idle issues, spose it might be bad vacuum lines