I recently had my EGR value cleaned out on my 2000 TL. Apparently the valve is defective on the 2000's (not sure what other years) and can be replaced for free by your dealer up until 80K. If you have not had this done and it applies to your car, make sure you get it done. If you have to take your car and pay for this, it will cost between $250 and $500. I'm sure one of the more enterprising members here can find the link to the TSB.