Code P1400. 2001 4.0 Ford Explorer

[mattwehrwein]

I just got done doing a timing chain in the 4.0 engine.

now the explorer has a p1400 code for Differential pressure feedback EGR Circuit low input.

I changed out the EGR valve (autozone brand) the EGR DPFE sensor and hoses from autozone, and I put a new egr tune in when I had the engine pulled for the timing chain. I also changed the egr solenoid as well.

None of that seems to help the code is still there. It Runs perfectly fine for a while but gets a rough idle that will cause it to stall out. Especially shifting into reverse and drive.

What else could cause this problem? Thank you for any help.

 

[EB4X]

I've read a vacuum leak can cause that code...and your symptoms would match that of a minor vacuum leak... maybe during process a / some vacuum lines got damaged/cracked/loosened..... spray some starting fluid around lines / connections and see if idle jumps up....

 

[mattwehrwein]

I've read a vacuum leak can cause that code...and your symptoms would match that of a minor vacuum leak... maybe during process a / some vacuum lines got damaged/cracked/loosened..... spray some starting fluid around lines / connections and see if idle jumps up....

I sprayed everywhere and don’t have any reaction. How else do you find a vacuum leak?

thank you

 

[EB4X]

Listen around for a hissing sound....