Insufficient & Excessive Flow???

[rusty-c]

Well, this one is new to me. My 98 Exedition (4x4;4.6L) ran fine for about 600 miles after nearly every component that could create a P401 code had been replaced then the check engine light came on and I ended up with both of these codes. Any ideas???

Thank....

[carlos80]

Originally Posted by rusty-c

Well, this one is new to me. My 98 Exedition (4x4;4.6L) ran fine for about 600 miles after nearly every component that could create a P401 code had been replaced then the check engine light came on and I ended up with both of these codes. Any ideas???

Thank....

I take you mean p1401(EGR insufficient flow). What components were replaced?
It's not always the components that cause faults. Like it was posted in another thread the ports for the EGR valve are very common for plugging up with carbon. These are located in the throttle body assembly.