goodnight1985
10-13-2009, 08:09 AM
My 97 GT is throwing a P0400 code (EGR Flow Malfunction). I have gone through the system and found that the cylinder head port for the EGR and the EGR tube (connects from the EGR valve to the cylinder head) where packed solid with carbon. I ordered a new tube from subaru and began cleaning the port on the head. The new tube will not arrive until Friday, so I have been cleaning the current EGR tube. I now have flow through the tube and through the port on the head, even though the tube is still very clogged, I can force a decent amount of air through it. I am still however getting the code after 2 drive cycles. My guess is the flow is still less than what it should be. Do the tube and the port need to flow at their maximum or can there be some deposits still in the path and not throw a code.
Also, when I operate the EGR valve manually at idle, the engine barely reacts. I know the engine should stumble, does this confirm that the EGR is still not flowing properly?
Also, when I operate the EGR valve manually at idle, the engine barely reacts. I know the engine should stumble, does this confirm that the EGR is still not flowing properly?