I have been searching for information on what the egr light on my dash means and havent had much luck. I have an 86 4wd wagon with the 1.8l engine it has a hitachi carb. Obviously I assumed that it means that the egr valve is probably faulty but i was wondering how it derives this information. The valve seems to move freely so i was wondering if some other part of the egr system could be at fault or the "sensor" that activates this light might be the problem.