I am a second owner of a 1994 Mercury Grand Marquis with 4.6L 281 cid V8 MFI engine and automatic transmission. I keep good care of the car and provide routine maintenance as needed although I have to admit its not at dealer recommended intervals. I have had the car since 2000 and on three or four occasions I have had problems with the EGR system. During the 1st occurrence I replaced the idle air control valve. On the 2nd occurance I replaced the EGR valve, EGR solenoid and DPFE. The third occurrence brought me into the dealer and they reported that I needed to get the EGR ports cleaned. This cost about $350. Now for a 4th time I am having similar problems. The check engine light comes on while the engine is running and I am at a stop or in slow traffic. I also get poor gas mileage and the engine pings & runs rough. I took the car into the dealer once again and they reported that I needed the DPFE replaced along with an EGR port cleaning.

In 6 years should I be having so many problems with the EGR system especially considering the dealer corrected the problem once themselves? I have no smoke coming out of the exhaust which indicates to me that I am not burning a lot of oil. Although I do have to admit that I need to top off the engine oil every now and then.

Does anyone know how easy or difficult it is to clean the EGR ports at home (if one is some what mechanically inclined)?