gmeeks wrote:
My CEL has been glowing for over a year at least... finally got the code pulled and got a P0401 & P0420. The mechanic that pulled the codes told me it needed a new EGR valve and to clean out the carbon, etc. Pardon my ignorance, because I know very little about cars, but I just noticed that the EGR vacuum hose has apparently melted or been rubbed raw and it is broken in two. Could this be enough to throw the CEL's?
P0401 means you don't have enough EGR flow. If the vacuum hose to the EGR valve is blocked or leaking, then the EGR valve won't open as it should, and you'll get this code. This doesn't necessarily indicate that the EGR valve itself is bad, and in fact, it most likely does not mean this. I understand that another common problem on Ford engines involves the EGR passages becomming blocked with carbon deposits, which would also cause a P0401.
P0420 means your catalytic converter is screwed, but wait 'til you get the EGR thing straightened out before you believe this. I've been told that EGR problems can cause wonky O
2 sensor readings, which could, in turn, cause a false alarm on the cat.