Here is the deal. I have been struggleling to get my 6.5 to run a little better. At light acceleration in town I get a blue smoke. The smoke also comes with jerking. I made an EGR block plate for between the EGR and manifold. The problem cleared right up. But it sets off the SES light. So I figure it must be in the EGR system. Today I hooked the vac. line from right next to the EGR to my vac gauge. It ran from 10" to 15" most times on light acceleration. When it was smoking it would be around 13" to 18", and would quit when I accelerated and vac would drop to 0. Is this normal and the solinoids are good? When I had the ERG off and put vac to it it would open and close good. Anyone with any experience with this?

The SES light comes on because your '98 has a MAF sensor that can tell your EGR is disabled. Sounds like completely normal operation as far as vacuum is concerned though.

Is there a way to check the EGR?

For operation? Sure, but your going to have to take those plates back out to do it, and you'll need a gauge that reads vacuum and that you can tap into the vacuum line that operates the valve.

The values stated above are EGR w/o plate as it came from factory. When I did have the plate in between, it ran good, no smoke, and therefore it must be in the EGR system? Took plate off and tapped into the Vac line at EGR to those values. If them values are "normal", then I could count out the solenoids as being bad. How do I check the EGR valve it's self?