Searched around, no help so I'll ask. This is my 88 with the L98, mostly stock with some exhaust work. Notice my EGR valve is either all open at 99% while cruising, or at 0 when letting off the gas or idling etc. Not showing the check engine light or setting codes but seems like it should not be this far open all the time. Could this be normal? What would a normal position be at 60 mph on level ground be?

 

It's pulse width modulated, but at 60 it will be wide open admitting inert exhaust gas into the F/A mixture diluting the mixture. EGR reduces NO during acceleration and under load. Basically what you have is normal.

 

Thanks for the reply. Guess I'm looking for trouble where there is none.