Bill, I don't know if it helps but the tiniest of exhaust leaks can cause big fluctuations in the exhaust gas readings. Try warming up the engine for a bit them get the car up on a ramp or over a pit if you can and get someone to hold a rag over the tail pipe end for a few seconds at a time and listen for leaks, i have had first hand experience of this of a car go from failed to passed on an annual inspection. Neil 82 Imp London England. ----- Original Message ----- From: "Bill Watson" <wwatson@xxxxxxxxx> > Oxides of Nitrogen have an average reading of 562.50 ppm with a maximum of > 1716 ppm. The Imperial failed with 2982.0 ppm. > > I suspect the problem is with the EGR. Any thoughts? > > BC AirCare stats show the Imperial averages to be way below the maximum > allowable limits. 1983 Imperials appear to be very clean running cars. > > Bill > Vancouver, BC