EGR Problems

[jscalvert]

I have a 2000 Protege LX. I've been having problems with the EGR for some time now. I replaced the EGR Valve a few months ago, but my check engine light is still on, and it reads 'Excessive EGR Flow' on the computer when i get a diagnostic done. I'm really not sure what the problem is. It's been stalling recently, and sometimes it takes a few extra seconds for the car to accelerate when i hit the pedal. I've also heard that this could be caused by the O2 sensor. I want to see if this is a problem I can fix myself to maybe save another trip to the shop.

Any help would be appreciatied. Thank You.

[Doug Tatham]

This is a very common problem. It isn't actually excessive flow, The computer measures differential pressure and misinterprets it as excessive flow. There is a tube coming out from the bottom of your intake manifold that goes to the EGR valve. It builds up carbon and other deposits, then blocks the flow. The actual problem is low flow despite what the computer thinks. Remove your EGR valve and your throttle body. Spray carb cleaner into the hole in the bottom of the intake manifold and the liquid will come out the place where the EGR valve attaches. Clean the port out thoroughly and everything will be fine for 80 K miles or so. You may want to put some shop towels behind the port before you clean. If you have too much carb cleaner left in the manifold you're going to have trouble starting it and a lot of white smoke for about 5 minutes.