92MaroRS

First id like to say i read the tech article. I read my codes at work today, came up with a code 32, EGR diagnostic Sw, Signaling Incorrect, EGR Valve operation. now the SES light comes on once in a while, maybe once a month if that, today seemed to be the special day it came on, the tech article seemed like it was more geared twards a constant on light, what should i look at or what could be the cause?

Benm109

Assuming your car's TBI, first thing I'd do is take the air cleaner off and check condition of the vacuum lines. They get corroded, gummed up, cracked, etc. over time. There's only 2 of them, one goes from the TBI unit to the EGR vacuum solenoid, while the other goes from the EGR vacuum solenoid to the EGR valve itself.

Next, try pushing up and down on the back side of the EGR valve, and see if the diaphragm moves up and down freely. Try applying vacuum to the EGR valve, and see if the diaphragm moves and see if the EGR valve will hold the vacuum(this is assuming it's a negative backpressure EGR valve, to check what kind it is, look on the EGR valve for a P or an N stamped somewhere on the top, because a positive backpressure EGR valve will not move with vacuum applied to it). If it doesn't move freely or doesn't hold vacuum, then the diaphragm may be leaking, which means you need a new EGR valve. If it does move and hold vacuum, then try removing the EGR valve, and cleaning the EGR valve and the EGR passages. The passages get clogged up with carbon over time and can cause problems.

One more thing to check is the wiring to and from the EGR vacuum solenoid. If I remember correctly, one wire should be a 5 volt reference while the other wire is a ground.