The EGR will kick on its own code in the computer, so I would say no to that. Also, does the pressure from the exhaust seem to be normal or weak? Can you hear any rattling or hissing from the exhaust? If there is a large enough vacuum leak (intake) or exhaust manifold leak it could be causing the O2 sensor to kick the light on. It will recognize the exhaust as being saturated.
Let me know if this helps.
Saturday, January 10th, 2009 AT 6:22 PM