The EGR valve itself is fine with that code. The EGR valve is bolted to the plenum. Rebooting the PCM involves disconnecting the battery for 20 minutes.

You can Suck Test the valve by removing the green emission hose / attaching a 2-3 foot length of hose in it's place and suck on the hose like your drinking a milkshake while the engine is running. If the idle deflects while doing this and the vehicle almost dies - The valve is working properly. If nothing happens / the valve is bad.

The DPFE is here -



Rectangled box. NOTE: Yours is black plastic and has two hoses attached.

 

Thanks everyone for your contributions, but the questions on accessibility and degree of difficulty have not been addressed. Just where is this valve located on this particular vehicle( F-150, Long bed, 4.6 engine, A/C), and how much time should I set aside for it? Is it near the firewall, for example?

I've yet to open the hood to peek in and look around being I leave for work in the morning and arrive home when it is somewhat dark.

Thanks again, guys.

 

Alright , but when the problem still persists after changing the valve , just come back here and read this thread again.

Scale 1 - 10, this is about a 4.

The valve is pictured above (shiny saucer looking thing) . Look under your throttle body cover , you can't miss it.

 

Thanks, JBrew. So you would completely replace it and not just simply clean the old one?

Thank you.

 

Sorry , what problem are you having?

PO401 = Your EGR valve is good ( 98% of the time )

PO402 = Valve is bad.

BTW - I wouldn't clean that valve , - The diaphragm is fragile and won't take solvents.

 

JBrew:

As I mentioned upstream, I had the engine diagnosed after the "Service Engine Soon" light came on last week. The reading came back with a "PO401" designation reading "EGR Insufficient Flow Detected". I heard that components to this valve get clogged up, thus my question about cleaning it out versus replacing it.

 

I suggest you look up PO401 . I have explained this many times. Sorry , you have to do some of the work I guess. Read this thread again for starters. I don't know how to get you to understand. We all work and have things to do as well.

 

Try This -

PO401

1. Clean area within green outline.

If that doesn't work, replace sensor inside of the blue outline.

2. DPFE Sensor.

 

Not all 5.4s have an EGR valve. So it's not missing. It was never there.

 

We figured that out 11 years ago, but thank you.

 

off topic, i have a 99 expy and live in ma as well it pass when it was within 15 years emmisions requirement. Because of age it doesnt matter one reason why i wanna keep it.