91 Civic NOX problem
 

My 91 Civic 1.5L FI has failed NJ inspection for NOX at about 3 times the
allowable level. Normally this is a clear EGR issue. I have both Haynes
and Chilton books and neither clearly identifies where the EGR is located,
and in fact if there's one at all! Can anyone tell me if I have one, where
it is, and how to test?