91 c1500 2 wheel drive 350 mileage 215535
need to find out which orifice washer to use when you don't have the o.E. Part number to go by.
the staff at the parts store that I bought the new egr valve at could not help me to find the right orifice washer. The paper work that came with the egr valve did not have the washer number from the old egr on the selection chart. Not even sure the egr I took off was the correct egr valve for this truck. Not sure if it is a good idea to use same washer number for new egr.
Are you sure its the valve and not a plugged passage or bad egr solenoid. With valve on manually pull valve on, engine should come real close to stalling. If not passage in intake is plugged, I only suggest this because of mileage on truck. OEM valve might be the way to go, no washers, they come correct out of the box