P0401 - Replaced EGR abd DPFE - what next?

[Johnny Glenn]

Thanks for looking in -- I've replaced the EGR and DPFE but still have insufficient flow! I do here a (leak) coming from the EGR vacuum regulator but feeling around back there I couldn't pinpoint leak. Once the vehicle is warmed up it begins to lope at idle but runs fine while driving. Any ideas - should I replace regulator or is the leak most likely a hose? Also for future reference is there a way to test EGR, DPFE, and Vacuum Regulator instead of replacing parts and crossing fingers? Thanks

 

[Runnin'OnEmpty]

The two vacuum hoses coming down from the DPFE are the
usual culprits for a vacuum leak. They tend to form cracks from
the heat that are hard to see. I'd replace them both and see
if that clears it up.....

 

[Johnny Glenn]

thanks -- that makes sense - my problem got worse when I replaced the DPFE, I probably loosened the lines are made them worse - thanks again - I'll give that a try.

 

[2000StreetRod]

No DPFE vacuum connection

On my 2000 SOHC there is no vacuum connection to the DPFE. The two hoses that connect to the DPFE are connected to the EGR pipe before and after the orifice to determine flow rate.

See my EGR System O&T for more information.

 

[Johnny Glenn]

I'm working on an 02 Ex 4.0 and the vacuum regulator is a part of the EGR system with several lines attached and located @ the rear of valve body. There's not much room back there and a vacuum sound seems like it's coming from there but I haven't had luck in determing source as of yet - I'll try the DPFE hoses today and maybe when I was replacing DPFE I pulled one of the lines loose from the regulator?

 

[Johnny Glenn]

Posting results - I found the leak, it was the pipe connected to the EGR and possibly the EGR gasket. I put some teflon on the threads for it to seal better and some sealant on the gasket - running like a Ford again.

 

[2000StreetRod]

Congratulations!

Thanks for posting the solution.