1990 Blazer code 32

[OSDCrusher]

Recently the "service engine soon" light came on my 1990 Blazer. I scanned for codes using the paper clip method. I got a code 32 (EGR SYSTEM). So I put in a known good, working, negative backpressure EGR Valve from a different TBI Blazer, which did run good before I pulled the EGR Valve. I drove it around that day with no more SES light. Yesterday I was driving it and the SES light came on again. So I scanned for codes again and got code 32. I have noticed that I have been getting bad gas mileage and a foul smell from the exhaust (which has no catalytic converter present.) The truck also has a new Delphi IAC Valve. The engine runs good and has plenty of power, no hesitation or bucking and the injector spray pattern looks very good.