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Question I have a 1985 Toyota Corolla with 88 K miles. I live in Illinois where we have state emissions testing every 2 year. In past years, the car passed well within state standards. This year, however it failed. A mechanic adjusted the timing, and the car passed. However, it did not pass by the wide margin it had in the past. The relevant data are: State Standards: HC(ppm)< 220; CO(%)< 1.20; CO+CO2> 6.00 Tested 4/12/97 HC 17 ; CO 0.00 ; CO+CO2 11.45 Tested 4/17/97 HC 266 ; CO 0.03 ; CO+CO2 10.55 Tested 4/22/97 HC 93 ; CO 0.00 ; CO+CO2 10.23 Should the fact that the HC reading jumped from 17 to 93 ppm, and the CO+CO2 fell from 11.45% to 10.23% be a cause for concern? Should I be looking for something else? I did tested the EGR system per Toyota Shop Manual procedures, and it passed all tests. Perhaps this is the original catalytic converter showing its age?? Any suggestions would be greatly appreciated. Paul

Reply On your 1985 Toyota Corolla, the increase of hydrocarbon emissions and decrease in carbon dioxide emissions indicate a slight loss in combustion efficiency. Please inspect your vehicle for any maintenance or repairs that may be due. A diagnostic check may be in order to determine the need for any repairs. The emission levels indicated on the test dated 4/22/97 are not high enough to create any concern as those emissions could be considered normal. Angelo Silverado Auto Service