yes having the cracked elbow intake tube has hurt my gas mileage BIG TIME. But how do i know i need to replace the DISA valve? Do i assume if the elbow intake valve is bad that the DISA is shot? thats 240 bucks i really am not looking to spend but will if i have to.

car seems smooth ride now, just the cracked elbow tube which i'll replace as soon as i get it.