Washers are for universal types because fits hundreds or more engines.
ACdelco, Standard and other units like above isn't same and you likely measure the wrong place. This type is gas metered farther in the unit and can't measure w/o taking apart. Or the opening work w/ the inside valve part that move down in the orifice IOW you might measure total opening but doesn't mean much.
When possible, this type work better because can't leak like loose washers in universal ones.
cebix
NOV 18, 01:11 PM
I thought that might be the issue and measuring like I did means probably not much. However the universal one with my washer that matched your measurement was running pretty good but with a little stumble at some RPMs. This one however seems to run good all through the RPM range. Conclusion: don't buy universal EGRs as it's a hit or miss thing especially if you don't know if yours is original.
To not be misunderstood I'm thankful for your measurement since it let me pinpoint what the issue was.
[This message has been edited by cebix (edited 11-18-2019).]
