1986 Chevy Cavalier egr code

I have an 86z24 cavalier with the 2.8 and 4sp, lately im getting a code32 - egr system failure ... ive replaced the egr and now am still getting the code, not at turn key but sometimes after 15 - 20 miles of driving. This egr is the vacuum type with no electrical connectors, my question is .... what sensors or connectors are sending my cars computer the egr code as failed ?? could the O2 sensor be setting the code 32 even tho i have no code for an O2 sensor?? im lost as to why this code is showing