I have a York gas forced furnace and my problem is on start up I observe the sequence of operation and after the igniter glows the gas valve opens and gas passes through to the burners closes to the valve (sometimes 2 burners ignite) the others farthest from the valve either don't ignite or they're late causing the unit to turn off. All Burners are clean, can the gas valve be the problem?

The burners themselves may be clean but I'd bet a weeks pay the problem lies in the carryover tube or crosslighters. A carryover tube is a small tube is holes or a slot which carries the flame from the ignition source to the opposite end of the burner rack. Crosslighters are usually on inshot style burners which look like small jet aircraft with the engine in the center & the crosslighters being the wings. It is very common to get rust in the crosslighters which blocks the gas flow.

Do they need to be replaced or just cleaned?

Do they need to be replaced or just cleaned?

Most of the time, just cleaned. If you have the inshot (jet plane) type of burners, a feeler gauge or other thin piece of sheet metal works well for cleaning out the "wings".