EGR Valve Help!

[Keeper62681]

According to the technicians, the reason my service engine soon light is on is because I need an EGR valve and solenoid for my 1999 Ford Taurus. What excatly are these parts for, is it necessary to get them replaced ASAP, and what should they cost? Thank you for your help.

[werty101]

before you do this take the throttle body off and see if the egr passages are plugged behind the gasket I put $80 in my 96 to find out it only took 15 min of cleaning to repair the light

[Vacuum]

I also have a 99 Taurus, with a 3.0L and over 150k miles. I recently had EGR issues also. The code that was returned was P404 (IIRC) EGR Insufficient Flow. After cleaning and checking the valve, testing the sensor, and testing the solenoid, with no problems evident. A mechanic that I know suggested that it might be a sticking lifter and suggested the following.

I changed the oil (5w30), and when adding new oil, I replaced a quart of the motor oil with a quart of Marvel Mystery Oil. I disconnected the negative battery cable and let the computer reset (I don't know how long this actually takes, but I let it sit for about 8 hours). Upon reconnecting the battery I started the car and let it run for a few hours. After driving it for a few days I performed a proper oil and filter change, with 4 quarts of 5w30 and .5 quarts of MMM. I haven't had any issues since (10k miles)